Important! Big problem with my 92 Corvette, does not start! Security lights blinking! HELP!! SOS

[tmkassin]

If I remember correctly the FSM says the radio is connected to the security system on a 92. This can cause the car not to start. I will have to look this up when I get to the shop tomorrow, but It seems to me it is an easy fix.

 

[boomdriver]

If you can find one :ugh
92/93 LT1 has unique ECM .

Long time not available new from GM and few used ones around ( for stupid $$$ when they are )
Rebuilt ( exchange ) is only option and from some accounts, guys have had more problems with the rebuilt ones than they had originally.

Really?
I had heard that before but I thought that availability had been resollved. I know there are lots of rebuilders out there, and there are none that have mastered that model ECM?

If thats the case, and he does need one, we should get our list of salvage stores put together so he has a chance. His harness needs to be straightened out for sure, before I'd install a repaired or rebuilt ECM. If, thats even his problem.....

This ECM availability issue sounds like other GM parts that have expired their 10 yr coverage...like my ABS for the 87. Practically one of a kind (bosch off-board diagnostic), I constantly fear damaging sensors because nobody has them. Part of the mechanical portion of the controller is available salvage only.
Corvette parts ....gotta love it.

 

[Bestdavidd]

I admire your effort and the work that you;re doing..

The ground wires that we want you to look at are the small wires from the main harness that connect to the frame in several different places. One VERY important place is the driver side of the engine, on the side of the block OR on the trans bellhousing where there will be 4 or 5 wires bolted to the trans or the block. Near there you should also see the small strap cable from frame to engine block.

The melted battery cable is coming from the starter turning too long. Only crank the starter for 3 seconds at a time...the longer it turns the more heat builds in the battery cables. The danger from this comes from cables not insulated touching other things that are opposite. Even the neg cable.

I think the VATS is OK, that is just what everybody blames when the car will not start. It is usually something else, but they always blame VATS because nobody understands what it is and how it works.

The more you describe this beautiful wiring job that somebody did to this poor car, the more it sounds like an ECM problem. Those are easy to replace, so hopefully the mechanic will tell you that is the problem.

The rest of the wiring???
A replacement wire harness sells for around $800 (or more) for a used one. It sure sounds like your car is a good candidate for one...

The ECM controls the engine with very exact voltage and sensor information. Levels of resistance are measured, exact voltage is known and used as a reference. The ECM and its wires are like your brain and the nerves in your body. You cannot go cutting into them and expect the brain to make your leg move or understand why it won't move anymore.:ugh

The ECM is about the worst place for a stereo installer to hook up for power...must have been his first day. That is probably where the trouble started...long before you ever got the car. Another thing to inspect is the fuse block backside. There are many many wires there that must be in good order. The front side is just for fuses...the backside is where the action is.

The pedal lights? you mean the floor lights? that is a small plug that only fits the light bulb in the floor panel. The driver side and passenger side are the same. You should have a small light bulb in the trim panel over the pedals. If that panel is gone,. then the missing wire for it has been stuffed up in the harness somewhere..

If you mean brake light wire, or switch, you will need an electrical drawing to see where that runs. It is part of a few other things. It is also one that has issues in the back of the fuse panel.

Good luck with the mechanic and the ECM test. Hopefully this will fix it and end your problems.

Okay, yesterday i took some pics to post here, here we go:




this is the ground cables in the passenger side, black thing is a short current was used to disconnect the battery to reset the computer and start the vehicle after 5 minutes when he wont start, that is well connected and checked by mechanic and thats not having problems.


that 2 cables with black tape are not connected with nothing, have a red ´´i dont know´´ like a conector... in the pics you can see that clearly, is that the pedals light that is not connected? if the answer is yes, the connector dont exist.



this is the cables from the stereo of the car, are connected to that ´´black box´´ that i dont know what is that, my mechanic tells me that is a voltage reductor, and its connected to the lighter... the thing that everybody use in the car to light a cigarrete. i dont know if it is well connected... the speakers are well connected, i doit by miself.



this is the voltage reductor... the black box, the stereo is connected to that... and that is connected to the cigarrete lighter, that blue cable is alone, does not have anything to connect to, i dont know what is that blue cable or to what works for, if anobody knows, please tell me.



this is the cables in the passenger side, that cables are disconnected, is from the speakers and i dont know why, but are not connected!
i have disconnected from the speakers, because the original speakers with the original stereo has original wires and original connectors, because i dont have a original stereo, i should disconnect that, and that connected cables ´´the old ones with the new ones´´ was the reason why my new stereo got burned.



another 2 more ground cables, from the passenger side, well connected like the other 2 in the drivers side, and no signals of corrosion or any other stuff.



another view from the 4 cables disconnected in the passengers side



relays in passengers side, theres another computer over there, but its too hard to get it out so i didnt try to get it out and check this out. in drivers side are like 4 or 5 relays too, 2 of them in passenger side, act when i pass the switch, so, are working fine.

4 pictures left, and i cant post more than 8 pics per post, so i will post again with new pics.

IF ANYBODY HAS THE ELECTRICAL PLANS OF THE CORVETTE C4, PLEASE TELL US! WILL BE SO MUCH HELP TO ANYBODY THAT HAS AN ELECTRICAL PROBLEM LIKE ME! IS FOR EVERYBODY, NOT ONLY FOR ME.

Having the electrical plans, we will know where they come from the cables, and where they will from. So it will be easier to solve problems.

 

[boomdriver]

yes, you NEED the electrical drawings.

I cannot help with this as it is. You need the drawings so you can see where the colors go and what they do.

Did you know that the stock Bose stereo speakers cannot work with other stereos because of amplifiers built into the speaker? This may be part of the problems with the stereo.

If you search E-Bay you can find a GM service manual for your car that will save you LOTS of money and time.

The important grounds are OUTSIDE the cabin. Not inside. There are many.

 

[Bestdavidd]

Really?
I had heard that before but I thought that availability had been resollved. I know there are lots of rebuilders out there, and there are none that have mastered that model ECM?

If thats the case, and he does need one, we should get our list of salvage stores put together so he has a chance. His harness needs to be straightened out for sure, before I'd install a repaired or rebuilt ECM. If, thats even his problem.....

This ECM availability issue sounds like other GM parts that have expired their 10 yr coverage...like my ABS for the 87. Practically one of a kind (bosch off-board diagnostic), I constantly fear damaging sensors because nobody has them. Part of the mechanical portion of the controller is available salvage only.
Corvette parts ....gotta love it.

y has the ABS and ASR lights on too, and traction control is not working, so, the car its hard to drive and in 1 time i almost crash them, with wet streets.

I hope my ECM will be good, i will know that on monday.


Here more pics:



this is the cables that goes to the positive of the battery, i think is a mess, but maybe was original like this.





here you can see the other ground cable, is connected to the negative of the battery, is that correct? the other 4 cables of ground must be connected to the battery too?




this is my car, a black corvette, lt1 engine, manual 6 speed transmission, i really love that car, and have upgrades, have SPEC stage 3 clutch, has chip, and has a turbomufflers on the exhaust, the oil changed every 3.000 miles with 5w30 sinthetic, etc... well mantained by me. And i fell bad when i see my car like this, in that conditions, full of dust, and no working! i just want to take a ride! and i cant :-(

if anybody can get the electrical plans, will be so helpfull to everybody here!

 

[Bestdavidd]

yes, you NEED the electrical drawings.

I cannot help with this as it is. You need the drawings so you can see where the colors go and what they do.

Did you know that the stock Bose stereo speakers cannot work with other stereos because of amplifiers built into the speaker? This may be part of the problems with the stereo.

If you search E-Bay you can find a GM service manual for your car that will save you LOTS of money and time.

The important grounds are OUTSIDE the cabin. Not inside. There are many.

yes, my car has BOSE speakers, and have 2 amplifiers, and that is disconnected, i just connect the speakers directly to the stereo to test, and everything is right like this! Sounds good and no problem.

And if i buy the service manual, in the service manual has all the cables? and i can solve my problem? if the answer is yes, i will buy that right now!

 

[Bestdavidd]

Ok here is what the CCM and ECM are

CCM = Central Control Module = It is located under the dash inside the car

ECM = Engine Control Module = It is located above the battery.

They are basically mini computers.

Before you proceed any farther if I understand correctly you are telling us that the radio had a smoking melt down after a couple of min. of being on and became very hot. Is that right?

_Yes bro! very very hot, but its interesting because the radio was there a long time, and one day just burned! with no reason!_the radio doesnt sound good NEVER, so i think is a bad connection in the radio, its a JVC, so if its a bad connection, the radio is too good! to has long time with that bad connection and dont burned up________

I believe you said that the car ran fine until you tried to use the radio and then the problems started. Is that right_

_Fine no, but the car stars, and when no starts, you just ´´knock´´ the computer 2 or 3 times and the car stars fine, like you knocking a door, same thing!________, but, when i removed the DVD screen (that its not connected) the car just dont start, so i dont know what im touched to being like this... i didint connect anything or disconnect, i just removed that! so it makes me think that one cable overther is in bad condition and its playing with me, but all the cables seems to be in good condition!! so im just going crazy...

As a first test you might remove the fuse to the radio and see if the car will start. If it does that will tell you that the problem is in the radio wiring or radio. By pulling that fuse you will also disable the PKE (Passive Key less Entry) but that will not keep the car from starting.

ok bro, i will do that test tomorrow monday when my computers arrive from servicing

As a side note here If in fact the radio did get hot and smoke then the radio fuse should be blown if it isn't than whoever put in the radio has done something to bypass it and again it should be completely removed. Do not install a new radio if that is the case until you find out what was done to the wiring to it

ok bro, i will do that!

Next I believe the engine cranks over but does not start. Is that right_____

yes! the engine moves, the starter works fine, but the car dont start! so i think the inyectors are not working because of the problem of the car, the computer dont send the signal to the inyectors and the car does not start, SECURITY lights blinking, so, big problem_______

Have you checked all the fuses in the fuse block____

yes! all the fuses are good, and the fuse of the radio didnt burned up when the radio burned up, the fusible of the radio is good! so im going crazy!______

When you clean the grounds and have the battery out to get to the ones behind it check the fuses in the big fuse block next to the battery.

every fuses are good, and grounds i think are good! check the pictures i posted!

 

[air1jpg]

Bose Stereo

You may want to run NEW speaker wires from your stereo to your speakers. You also may want to purchase 4 new speakers as well. The original Bose stereo that was installed in your vette ran on low impedence between the head unit and the amplifiers behind each speaker. If the person used the original speaker wires when he installed the aftermarket stereo, he created a problem. The original speaker wires are too small and were not designed to handle high impeadence from an aftermarket stereo. :ugh

 

[Bestdavidd]

You may want to run NEW speaker wires from your stereo to your speakers. You also may want to purchase 4 new speakers as well. The original Bose stereo that was installed in your vette ran on low impedence between the head unit and the amplifiers behind each speaker. If the person used the original speaker wires when he installed the aftermarket stereo, he created a problem. The original speaker wires are too small and were not designed to handle high impeadence from an aftermarket stereo. :ugh

THANKS! I WILL DO THAT! BUT, WHEN THE STEREO DISCONECTED THE PROBLEM WILL GONE? BECAUSE WHEN THE PROBLEM STARTED IN MY CAR, THE STEREO WAS DISCONECTED.

I ONLY WANT TO FIX MY PROBLEM AND USE MY CAR WHEN I WANT, NOT WHEN HE WANTS! :ugh

 

[John Robinson]

I looked for the schematics in my FSM but they are broken down into each circuit and there are probably 100 pages so I gave up the idea to scan and send them to you. The picture with the two cut wires that are taped on the ends may be for the brake and clutch switches Look up high on the pedal arm for a plunger switch that moves in and out when you push on the pedals. The picture that shows some wires connected by being twisted together. You might try to untwist them and then look for a wire that is the same color and gauge in that area. that is in another made up connector. If so and if the extra wire runs to something like that box. Then you probably can disconnect that as an add on piece and reconnect the like wires. I would think that if they were cut to interrupt and put something else in that circuit the ends would almost touch without pulling on them. One trick I use is to use a jumper wire with a 2 amp inline fuse and use it to connect the wires. That way if they do not go together the fuse will blow and protect the rest of the wiring. Again I think by good careful inspection you should be able to see were wires have been added and eliminate them. And of course it goes almost without being said but don't do continuity checks with the ecm connected because the voltage from the meter can back feed into the ECM. I learned that on a BMW motorcycle that had burned some of it's wiring and I remade the wiring harness.

 

[Bestdavidd]

I looked for the schematics in my FSM but they are broken down into each circuit and there are probably 100 pages so I gave up the idea to scan and send them to you. The picture with the two cut wires that are taped on the ends may be for the brake and clutch switches Look up high on the pedal arm for a plunger switch that moves in and out when you push on the pedals. The picture that shows some wires connected by being twisted together. You might try to untwist them and then look for a wire that is the same color and gauge in that area. that is in another made up connector. If so and if the extra wire runs to something like that box. Then you probably can disconnect that as an add on piece and reconnect the like wires. I would think that if they were cut to interrupt and put something else in that circuit the ends would almost touch without pulling on them. One trick I use is to use a jumper wire with a 2 amp inline fuse and use it to connect the wires. That way if they do not go together the fuse will blow and protect the rest of the wiring. Again I think by good careful inspection you should be able to see were wires have been added and eliminate them. And of course it goes almost without being said but don't do continuity checks with the ecm connected because the voltage from the meter can back feed into the ECM. I learned that on a BMW motorcycle that had burned some of it's wiring and I remade the wiring harness.

everything is good and connected, only thing is not connected is the light in the pedals, and i dont know where are the connectors and the cables to connect that.

another thing is not connected is a plasting piece, that is in the brake who has a hose going to the engine, and does not have the connectors or anything! Other things are well connected. Im searching for electrical plans of the car, to see what is good or what is bad, that week i have it for vacations, and i will spend all my vacations fixing my car, i will test that with a fuse and a cable to detect what cable is lost, good idea bro!

Im going crazy with that car... if anybody needs more pics, i have it! or if anybody has your c4 disarmed like me, please take some pics and post here to see the cables!!!! lost cables, and everything that a car in good working condition has.

thanks everybody for the help, tomorrow i will continue testing

 

[Bestdavidd]

everything is good and connected, only thing is not connected is the light in the pedals, and i dont know where are the connectors and the cables to connect that.

another thing is not connected is a plasting piece, that is in the brake who has a hose going to the engine, and does not have the connectors or anything! Other things are well connected. Im searching for electrical plans of the car, to see what is good or what is bad, that week i have it for vacations, and i will spend all my vacations fixing my car, i will test that with a fuse and a cable to detect what cable is lost, good idea bro!

Im going crazy with that car... if anybody needs more pics, i have it! or if anybody has your c4 disarmed like me, please take some pics and post here to see the cables!!!! lost cables, and everything that a car in good working condition has.

thanks everybody for the help, tomorrow i will continue testing

Hello everybody!

Today was the day of tests in my 92 corvette! im really tired and pissed out! I have many videos explaining everything, by the way, im going to explain too

http://www.youtube.com/watch?v=gTiz8TWnTHU

why the needle moves crazy? as seen hard to explain me to everybody, y just has recorded a video to explain better.

http://www.youtube.com/watch?v=B9iFRkd8qXU

this is the error codes that throws me when the vats does not have the aluminium body on, i just dont know why the codes changes when the VATS is with her body on.

When the VATS is with his aluminium body, the only code that throws me the car in 1. is C41 and H41, by reading all the papers, C is ``Current`` and H is ``History``, and the specification of the code is ``ECM Data Communications Lost``

So, what that fail means? What i need to fix to get my car start again?

http://www.youtube.com/watch?v=AKBZjSCmFWM

heres me explaining a little better the ``past´´ of the starting problem, and the wires that i dont have where connect! are not that much, are only a few, if somebody knows where that cables go, PLEASE TELL ME!!!! Will be so much helpfull to me....

http://www.youtube.com/watch?v=p3zLjJ7uL6g

here im I! testing and testing... and blowing my brain out thinking in ``what can i do to fix it´´, when i armed the VATS, with his aluminium body, the car shows me only 2 errors, the same 41 error that says ``ECM Data Communications Lost´´. now guys, i just tested everything i can, i only need somebody to help me to fix it! We know whats wrong, so, only least to fix that problem!!

I does not have experience, is my first corvette... nice welcome ha? i have experience is in Mercedes Benz, that was my only car, and i has 4 in my life and i want to have more in the future, i have the corvette because i just wanted to know the american cars, because im a little bit curious, and i LOVE that car! looks awesome! So i changed my 2003 Mercedez Benz ML 500 for that black beast of the 92....nice change? i dont know, but i dont want to regret and fix the car! if i cant, i would get back to germans and forget americans... and in the deep of my heart, i dont wanna do it :-(

http://www.youtube.com/watch?v=NTWkyaNd1ik

Here i go again, testing and testing.... i removed again the aluminium body of the VATS, and i just confirmed my questions, when the vats is nude, the car shows a lot of error codes... and when the vats has his clothes on, the vats only shows the real error codes of the car... curious ha? Im like a cat right now....

http://www.youtube.com/watch?v=uGMjLFwzVb0

http://www.youtube.com/watch?v=uGMjLFwzVb0
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Here i go again... almost at night, i spended all my day working on my corvette... and the car just dont start!.....im going crazy.... stereo works fine, and everything is working excepting the engine.... nice ha? I have a good stereo, a good car, and if i want to date a girl with my car must be in my garage because the car does not start, owesome ha? very deppresing....​

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Look guys... now i have a lot of time free, im in a short vacations of the university, and i can stay here connected all the day and testing all the day in my car, and if anybody wants to help me, please ask me and i do wathever you think to fix it! and i can send more videos and these stuff....​

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Thanks everybody for the help, with the videos, i think is more clearly everything....​

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Another interesting quote:​

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when the security lights blinks 3 times, in the cluster appear the number 545 (the 4 is very strange, and i dont know if its a number 4) and that number blinks with the security light, when hes off, the number is off too.​

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I have reseted all the codes of the car, and i have that information, the software of my car is 92AO235.​

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Some places in the guide that you send me says ``number 1 is enabled´´ but in some codes tells me a number like 240, that appears in the DOOR KEY SWITCH code, so i dont know whats happening.​

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in the video you can say the needle of the oil press moving crazy, thats normal in the corvettes guys?​

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Im just waiting for answers! im not too good in my english, im just still learning! but i do best i can! And i do double work with you because i want to everybody can understands me.​

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thanks everybody, im waiting here for opunions, comments or answers hnoes​

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[John Robinson]

Hope this helps you with the C41 Code


http://i285.photobucket.com/albums/ll72/John-68/DTC410002.jpg

http://i285.photobucket.com/albums/ll72/John-68/DTC410001.jpg

 

[John Robinson]

These may be easier to read than my first post
John

 

[boomdriver]

View attachment 3208View attachment 3207

These may be easier to read than my first post
John

C41 was probably the original problem...simple ECM com problem either in the ECM or the harness.; BUT, by jumping to conclusions about the VATS without ANY evidence and chopping things in/out, its been butchered now. Multiple layers of problems with the first hidden by the ones created ..
There is no point in him continuing without a full set of electrical drawings. The wiring harness MUST be straightened out before ANY conclusions can be made. Otherwise, there is no way of verifying test.

Just because a car does not start does NOT make VATS at fault.

A ck of the inj? noid lite? spark test? module test? coil test? fuel pressure test?

This deal begs for a FSM......not worth touching without one. They're all over EBAY. If there is an auto-electric shop around there...call a tow truck.

"the aluminum body of the VATS.." ????????? :confused :confused :confused :confused :confused

the ECM ? :confused it needs that.

 

[John Robinson]

C41 was probably the original problem...simple ECM com problem either in the ECM or the harness.; BUT, by jumping to conclusions about the VATS without ANY evidence and chopping things in/out, its been butchered now. Multiple layers of problems with the first hidden by the ones created ..
There is no point in him continuing without a full set of electrical drawings. The wiring harness MUST be straightened out before ANY conclusions can be made. Otherwise, there is no way of verifying test.

Just because a car does not start does NOT make VATS at fault.

A ck of the inj? noid lite? spark test? module test? coil test? fuel pressure test?

This deal begs for a FSM......not worth touching without one. They're all over EBAY. If there is an auto-electric shop around there...call a tow truck.

"the aluminum body of the VATS.." ????????? :confused :confused :confused :confused :confused

the ECM ? :confused it needs that.

So, what that fail means? What i need to fix to get my car start again?

That was his question on the C41 code and that is why I sent him the information from my FSM. I don't disagree with you about his needing the FSM. I was hoping that bit of information would get him started in going through the wiring nightmare he has. Also it should reinforce what we are saying about the grounds and the integrity of the whole system being needed for the ECM to work correctly and whatever was done before he got the car destroyed that. Until all the wires are correctly reconnected and grounded he can not begin to look at the hard parts (ECM, VATS, CCM, ETC) for his problems.

 

[Bestdavidd]

Hope this helps you with the C41 Code


http://i285.photobucket.com/albums/ll72/John-68/DTC410002.jpg

http://i285.photobucket.com/albums/ll72/John-68/DTC410001.jpg

Wow man, ahahaha, im just impressed! Thanks a lot John, i will do that test and i will be here with results, i hope good results

 

[Bestdavidd]

C41 was probably the original problem...simple ECM com problem either in the ECM or the harness.; BUT, by jumping to conclusions about the VATS without ANY evidence and chopping things in/out, its been butchered now. Multiple layers of problems with the first hidden by the ones created ..
There is no point in him continuing without a full set of electrical drawings. The wiring harness MUST be straightened out before ANY conclusions can be made. Otherwise, there is no way of verifying test.

Just because a car does not start does NOT make VATS at fault.

A ck of the inj? noid lite? spark test? module test? coil test? fuel pressure test?

This deal begs for a FSM......not worth touching without one. They're all over EBAY. If there is an auto-electric shop around there...call a tow truck.

"the aluminum body of the VATS.." ????????? :confused :confused :confused :confused :confused

the ECM ? :confused it needs that.

thanks boomdriver! i will do that test and i will write here again!

Anybody know what that lost cables in my car comes from?

The needle of the oil pressure its normal that being that crazy?

mmm im just thinking that i have one problem, one cable doing bad contact with another cable, and that thing is the thing that is going me crazy! i hope that, and i hope to fix it.

I sent an e-mail to a man that he specialice in electrical problems, and you know what? he tells me that:

Hi David,
Unfortunately the 1992 Corvette is a electrical nightmare. The problem with
the vehicle not starting could be many things, but If you use to "knock" the
computer to start it, then I would suspect that first. You can try removing
the computer and placing in the freezer for a hour or so, this will shrink
the solder connections and may temporarily allow you to start the vehicle if
the computer is the defective part.
Thanks,
Mike Macaluso
ENORMIS Mobile Specialties Inc.
5250 Buffalo Rd.
Erie, Pa 16510
814-899-8885
www.enormis.net

So, in other words, he tells me ``explode your head trying to solve that problem you, not us´´..... in what problem im in?.... im going crazy! but i will do all that test thanks a lot guys!:W

 

[vetteoz]

C41 was probably the original problem.
Just because a car does not start does NOT make VATS at fault.

As I stated back in post #7
DTC 41 ( loss of serial data link ) gives same symptoms as VATS shutdown.

From the manual.

The FEDS system operates in conjunction with the UTD and PASS Key systems.
It uses a password exchange system between the ECM/PCM and the CCM after the correct PASS Key has been sampled to enable fuel delivery to the engine.
The password exchange uses the serial data line between the ECM/PCM and CCM.
The ECM/PCM generates a password, scrambles it, and sends it to the CCM over the serial data line.
The CCM unscrambles the password and selects the appropriate response password.
The CCM then scrambles the response password and sends it over the serial data line to the ECM/PCM.
The ECM/PCM unscrambles the response password and compares it to the correct response it expects for the password originally sent.
If the response from the CCM was correct, fuel delivery is enabled and a message noting that FEDS has been successfully completed is sent to the CCM .

simple ECM com problem either in the ECM or the harness.

Not that simple, many have invested lots of time and $$$ have still not resolved the problem.
Is a well documented problem with this in 92 / 93 cars ; many unresolved by ECM repair/ replacement
http://forums.corvetteforum.com/c4-scan-and-tune/1218103-which-is-failing-ecm-or-ccm.html
http://forums.corvetteforum.com/c4-...-while-hot-error-code-h41.html#post1574977144
http://www.digitalcorvettes.com/forums/showthread.php?t=35360

Problem is not helped by having a major splice of all serial data cables behind dash; if one of the links is to ground anywhere in the car then the link fails.
Only way to find a fault is to disconnect splice and meter out each link individually to find the fault

Plus ground problems as you previously mentioned
http://www.digitalcorvettes.com/forums/showpost.php?p=501965&postcount=17


Ultimate fix for many is to have VATS deleted from the tune so ECM does not require the serial data link to the CCM ( wherever the fault may lie )

 

[boomdriver]

As I stated back in post #7
DTC 41 gives same symptoms as VATS shutdown.


Not that simple, many have invested lots of time and $$$ have still not resolved the problem.
Is a well documented problem with this in 92 / 93 cars ; many unresolved by ECM repair/ replacement
Which is failing? ECM or CCM? - Corvette Forum
ECM Problem? Trouble Starting While Hot - Error Code H41 - Corvette Forum
pulling my hair out - Corvette Forum : DigitalCorvettes.com Corvette Forums

Problem is not helped by having a major splice of all serial data cables behind dash; if one of the links is to ground anywhere in the car then the link fails.
Only way to find a fault is to disconnect splice and meter out each link individually to find the fault

Plus ground problems as you previously mentioned
Corvette Forum : DigitalCorvettes.com Corvette Forums - View Single Post - pulling my hair out


Ultimate fix for many is to have VATS deleted from the tune so ECM does not require the serial data link to the CCM ( wherever the fault may lie )

I thought the ECM was being tested and was coming back either good or needs to be repaired.. What happened to that I wonder?

From what I see....he needs a FSM electrical books with the cartoons....
and,. likely an ECM.

Get the wires right before doing ANYTHINGA ELSE....Thenplug in the ECM andstart to diagnosis.

One thing at a time........