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

[Bestdavidd]

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 )

thanks vetteoz, i readed all the posts and one guy says that the ``sys`` light (i dont know what is that light) flashes when the original stereo is not installed, and he says that if you install a resistor the circuit will close and that light will off. Sys are security light?

If you have an aftermarket radio, it can cause the CCM to set error code 72. If that's the case, the SYS light will continue to flash until you install a resistor in the Dimming control line to complete the circuit.

Whats the dimming control line?


I hate when people install PIECES OF SHIT in the cars... cars must be ORIGINALS, like they come from factory!!!!! The problem started in my car since the previous owner changed the stereo (he told me that)

And how can i do that?

Ultimate fix for many is to have VATS deleted from the tune so ECM does not require the serial data link to the CCM

i dont know how to do that, i have readed and readed all the post and im pissed... im not the only one with that problem, so, its not my fault, its GENERAL MOTORS fault! So... i dont know what to think.

Now the computer in the car that comes in the engine is in the freezer to do a test, if the car starts fine, the problem is that computer!

 

[Bestdavidd]

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........

yes boomdriver i want to do that! to put the wires right! but what can i do that? i post here in videos and in pics my lost wires, and nobody helps me with that, nobody knows where they come or where they go.

And how can i get the plans of the wires? to check that everything is ok? i dont know why.... or where i can got the plans, for that reason im here.

Another question, im the only one with that problem here? anybody has a 92 or 93 vette and does not have that problems ever? im just worried about it...:ugh

 

[vetteoz]

one guy says
If you have an aftermarket radio, it can cause the CCM to set error code 72.
If that's the case, the SYS light will continue to flash until you install a resistor in the Dimming control line to complete the circuit.
Whats the dimming control line?

I mentioned that back in post #15 on the 1st page.
The CCM expects to see a certain resistance on the wire that dims the lights in the stereo.
When you put a non factory stereo in this figure changes so the CCM throws a code

Does not prevent car from starting however

 

[Bestdavidd]

I mentioned that back in post #15 on the 1st page.
The CCM expects to see a certain resistance on the wire that dims the lights in the stereo.
When you put a non factory stereo in this figure changes so the CCM throws a code

Does not prevent car from starting however

vetteoz i find that: installing a aftermarket stereo ( or removing it ) will nearly always throw a code because the CCM is not seeing the certain voltage
on the stereo dimming circuit that it sees with stock stereo; hense it puts a code up

See Pg 6 ,
#11 in the CCM link I posted

and i dont understand that, please explain me better because i dont undestand.

Here i go again, after full test, my car does not start, and throws me the code 41, reading and reading in internet i found that: ECM Problem? Trouble Starting While Hot - Error Code H41 - Corvette Forum

look at the pictures, 2 more pages of the error 41 and troubleshoting too... are that another pages from the manual that somebody send me here? or there is another manual?

im trying to get all the information i can of the code 41, because for that code my car does not start, im just going crazy....

i test my car with the computer in the freezer for more than an hour, i connected really fast to the car, and nothing happened, so, my engine computer is good! i think! i dont know why in the past i knock that computer and the car just start, i cant just understand....

Another thing my friends, i dont have really clearly whats CCM, and ECM, and other stuff, can explain me better wich is one?

I know is the black computer on the engine, up the battery, whats the name of that?

and the computer that has the aluminium body that is behind the stereo, that nude tells me a lot of codes and with his aluminium body tells me only 1, whats the name of that?

and where is the other? is the computer that is on the passengers side behind the dash? i just cant acces to that computer, its so hard...

Reading and reading the manuals, i just wanna know that to understand better everything.

That corvettes are electrical nightmares!!! I just cant sleep! thinking in how to fix my car! im going crazy... i think in fix my car every 5 seconds! My head will explode!

 

[vetteoz]

i dont have really clearly whats CCM, and ECM, and other stuff, can explain me better wich is one?
I know is the black computer on the engine, up the battery, whats the name of that?

That is Engine Control Module , ECM , the Computer

the computer that has the aluminium body that is behind the stereo, whats the name of that?

That is Central Control Module , the CCM

and where is the other?

They are only two units we are talking about here

 

[toptechx6]

Stop wasting your energy blaming General Motors or the jackass who installed the stereo, instead buy a Factory Service Manual here
Service Manuals, Owner Manuals, Wiring Diagrams, Service Bulletins - Helm Incorporated or on Ebay.
Book #2 of the FSM set has all the diagnostic charts and wiring diagrams for your car, use it to sort out DTC 41.
An alternative as vetteoz mentioned is to have a tuner remove PASS KEY or VATS from the ECM. Here are two that can do it for you.

PCMforless.com

madtuner.com - Home

 

[John Robinson]

Stop wasting your energy blaming General Motors or the jackass who installed the stereo, instead buy a Factory Service Manual here
Service Manuals, Owner Manuals, Wiring Diagrams, Service Bulletins - Helm Incorporated or on Ebay.
Book #2 of the FSM set has all the diagnostic charts and wiring diagrams for your car, use it to sort out DTC 41.
An alternative as vetteoz mentioned is to have a tuner remove PASS KEY or VATS from the ECM. Here are two that can do it for you.

PCMforless.com

madtuner.com - Home

I have done a little research and found this site DIY Auto Repair | Do It Yourself Auto Repair | Chilton DIY. If you go there you can also get on line the schematics for your car directly from the internet. It may take a little searching of their site but I think you are computer literate and it should not be a problem for you. I don't know if you can get the on line schematics from Helm but if you can they would be my first choice and then the site I found would be my second.

Good Luck and hope this gets you what you need to unscramble you wiring nightmare.

 

[toptechx6]

I have done a little research and found this site DIY Auto Repair | Do It Yourself Auto Repair | Chilton DIY. If you go there you can also get on line the schematics for your car directly from the internet. It may take a little searching of their site but I think you are computer literate and it should not be a problem for you. I don't know if you can get the on line schematics from Helm but if you can they would be my first choice and then the site I found would be my second.

Good Luck and hope this gets you what you need to unscramble you wiring nightmare.

That is a good point John. Another online source for wiring diagrams direct from the FSM is Alldata
Do it Yourself Auto Repair & Auto Repair Shops - ALLDATA
A single vehicle subscription is about $27 and includes everything in the FSM, plus access to TSB's , labor time and other worthwhile information.
It can be more difficult to use than a paper manual however because the troubleshooting charts frequently require flipping from one section to another, but it is a low cost option.

 

[boomdriver]

That is a good point John. Another online source for wiring diagrams direct from the FSM is Alldata
Do it Yourself Auto Repair & Auto Repair Shops - ALLDATA
A single vehicle subscription is about $27 and includes everything in the FSM, plus access to TSB's , labor time and other worthwhile information.
It can be more difficult to use than a paper manual however because the troubleshooting charts frequently require flipping from one section to another, but it is a low cost option.

cool....
now if he'll do it.
This car ain;t going anywhere until that harness gets straightened out.

A stereo connected to the ECM? Misc wire cut and left hanging from the dash & IP harness? Disconnecting the ECM and trying to start thinking that was VATS..."touching" the CCM and it starts? touch how I wonder? with a hammer? a battery jumper cable? a faith healer?

naw..
this needs the guidence and direction of a FSM, once the harness has been repaired and restored. Until then, there're ain;t a chance.

People HAVE TO understand that these electrical systems are far too complicated to repair at home unless you have a FSM, the proper tools and training AND some diagnostic equipment.

This a'int your grandfathers Oldsmobile......

 

[Bestdavidd]

That is Engine Control Module , ECM , the Computer


That is Central Control Module , the CCM

They are only two units we are talking about here

thanks vetteoz! now im clearly! CCM is the devil, the vats right? i call that evil thing ``vats´´, welll.... thank you

this picture is from your car?

i sought in internet original stereos for my corvette and is a lot of expensive... cheaper i found on ebay are 300$... wow... i want an original stereo, and i will find one to keep my car original like they come from factory

 

[Bestdavidd]

cool....
now if he'll do it.
This car ain;t going anywhere until that harness gets straightened out.

A stereo connected to the ECM? Misc wire cut and left hanging from the dash & IP harness? Disconnecting the ECM and trying to start thinking that was VATS..."touching" the CCM and it starts? touch how I wonder? with a hammer? a battery jumper cable? a faith healer?

naw..
this needs the guidence and direction of a FSM, once the harness has been repaired and restored. Until then, there're ain;t a chance.

People HAVE TO understand that these electrical systems are far too complicated to repair at home unless you have a FSM, the proper tools and training AND some diagnostic equipment.

This a'int your grandfathers Oldsmobile......

i want to keep the dash out, entirely dash.... and test wire and wire.... i dont know if its a good idea, but i gonna do it, a lot of job, yes... but i hope it works, whats your opinion?

Electrical is not complicated, you only need to find where goes that wire and thats all, and my problem is like a little bit complicated.

Last owner told me ``car runs fine for a month with no security lights of anything´´ in ocations, and other ocations car just dont start (like my case now) so i think is 1, ONEEEEEE cable that loose the contact, or that cable is broken and sometimes do contact and sometimes not. but how can i find that wire? with the ton of wires that my car has? thats the real job.

And im not blamming about GM, im telling the true, because theres A LOT OF PEOPLE with the same problem... A LOT!!!!!! so? my fault? Mi ML 500 Mercedes has an aftermarked pioneer DVD player stereo, touch screen, has a plant, bass, etc.. and never gave to me problems like this, the stereo is not connected to the security of the car ``GOOOOOOOD IDEA´´ and nothing like this, wires are so much ordenated and well directed, and other stuff is a lot of bad comments ``i have years trying to solve my problem and i cant´´ or ``92 corvettes are electrical nightmares´´ that comments are.... like a ton comes over me! :bash

 

[boomdriver]

i want to keep the dash out, entirely dash.... and test wire and wire.... i dont know if its a good idea, but i gonna do it, a lot of job, yes... but i hope it works, whats your opinion?

Electrical is not complicated, you only need to find where goes that wire and thats all, and my problem is like a little bit complicated.

Last owner told me ``car runs fine for a month with no security lights of anything´´ in ocations, and other ocations car just dont start (like my case now) so i think is 1, ONEEEEEE cable that loose the contact, or that cable is broken and sometimes do contact and sometimes not. but how can i find that wire? with the ton of wires that my car has? thats the real job.

And im not blamming about GM, im telling the true, because theres A LOT OF PEOPLE with the same problem... A LOT!!!!!! so? my fault? Mi ML 500 Mercedes has an aftermarked pioneer DVD player stereo, touch screen, has a plant, bass, etc.. and never gave to me problems like this, the stereo is not connected to the security of the car ``GOOOOOOOD IDEA´´ and nothing like this, wires are so much ordenated and well directed, and other stuff is a lot of bad comments ``i have years trying to solve my problem and i cant´´ or ``92 corvettes are electrical nightmares´´ that comments are.... like a ton comes over me! :bash

Most of the "problems" come from people messing with a very complicated computer system when they know nothing about it.

Get the Service manual for the electronics and then you can get it corrected. FIRST.......you MUST get the wire harness correct. The only way that can happen is with the book.

BTW..the service manual is 2 books. Like I said, its very complicated.

 

[vetteoz]

CCM is the devil, the vats right? i call that evil thing ``vats´´,

VATS is a function inside the CCM which performs many
functions

i want an original stereo, and i will find one to keep my car original like they come from factory

If you install the resistors as shown below they will remove the dimming circuit fault code .

The resistors are needed if stereo is removed or an aftermarket stereo installed

 

[Bestdavidd]

Most of the "problems" come from people messing with a very complicated computer system when they know nothing about it.

Get the Service manual for the electronics and then you can get it corrected. FIRST.......you MUST get the wire harness correct. The only way that can happen is with the book.

BTW..the service manual is 2 books. Like I said, its very complicated.

and when can i buy that books bro?

 

[vetteoz]

and when can i buy that books bro?

1992 Corvette Shop Service Manual Set - eBay (item 310306466947 end time Mar-28-11 14:17:33 PDT)

1992 Chevrolet Chevy Corvette Service Shop Manual Set - eBay (item 160554703203 end time Apr-03-11 10:52:21 PDT)

Or on Cd
1992 CHEVROLET CORVETTE Shop Service Repair Manual CD - eBay (item 370495282386 end time Apr-21-11 09:27:12 PDT)

 

[Bestdavidd]

1992 Corvette Shop Service Manual Set - eBay (item 310306466947 end time Mar-28-11 14:17:33 PDT)

1992 Chevrolet Chevy Corvette Service Shop Manual Set - eBay (item 160554703203 end time Apr-03-11 10:52:21 PDT)

Or on Cd
1992 CHEVROLET CORVETTE Shop Service Repair Manual CD - eBay (item 370495282386 end time Apr-21-11 09:27:12 PDT)

a friend right here has that books! im gonna tell him!!!

today i pulle out ALL the dash of my car... ALL!

Cluster and everything is OUT now! Im sick of it! My vacations only least a few days and i need to fix my car now!

I want to pull out the wires of the car, ALL OF THEM! and testing 1 by 1, a lot of job, but im gonna do it.

Disarming a corvette is another nightmare! Engineers of chevrolet do EVERYTHING in that car like they doesnt want that anybody disarm a corvette, SO HARD! Everything!!!!!! Every piece you try to pull off, its a lot of job....

I have changed the evaporator in my ML 500 and was A PIECE OF CAKE compared to that car.

Im just finishing to pull out the car, is more than midnight and im still working on the car... Im still thinking ``germans do it better´´ next sport car i will buy, will be a Porsche, no more corvettes, too much problems to me, and if i will buy a corvette again, will be one 2008-2010, that is everything new and no problems!

heres 2 pics of my job:

im doing fine doing that?

Another thing, int he dash on the passenger side, when you remove ALL OF THAT, you find 3 more computers, and the bigger one sounds when the car throws to you error codes.

I connected the cluster and the air conditioning (its ennoying, air conditioning starts everytime i pass the switch on) and the other stuff that tolds me ``service ASR and Service ABS´´... well... and the car throws me a loooooot of codes! Im goind crazy! i just want to test with no more than the wires and the cluster and te computers to test and i cant because the car throws a ton of codes, i should know it when i arm the car again? not fair.... Another bad stuff that i looked about my car:

Every computer has grounds by connecting the computer to his original position to make ground, WHY???????????? That desing CREATES PROBLEMS! if i will be a GM engineer i would pass everything with ground wires, and all ground wires together, ground fails? the wires of the ground are all together and easy to find! Easier to repair... that car shows me its so amazingly hard to repair....

Well, i hope im doing right doing that :eyerole:eyerole:eyerole:eyerole:eyerole:eyerole:eyerole:eyerole

Im tired.... im going to sleep to tomorrow keep up here.:ugh:ugh:ugh:ugh:ugh:ugh:ugh:ugh:ugh

Hope works:eyerole

 

[toptechx6]

:L Hey good luck! You may want to try a Porche forum, you don't seem to listen to anyone here. At least 3 members have provided links to sources of wiring diagrams and diagnostic information, maybe the Germans can help.

 

[Bestdavidd]

:L Hey good luck! You may want to try a Porche forum, you don't seem to listen to anyone here. At least 3 members have provided links to sources of wiring diagrams and diagnostic information, maybe the Germans can help.

I love that car, but im hating my car because the problem, and i hate GM because im not the only one.

Im listening everyones here, and i have do all the test that you send me and everybody sends me. And i didint have results, for that reason im going crazy and im looking for a broken wire in all the wires.

Everything is good in the plans on the engine of the error 41, also i put all the cables of the spark plug new a few weeks ago and no problems, the car runs well, its a nightmare to change that cables in one side too, you must pull out the alternator... etc....

im just no blaming or anything else, im just telling the truth, corvette of 92 its so hard, but SO HARD to work in it, everything is so complicated.... GM engineers dont think in mechanics. I say the same thing with BMW, i haved an 850CSI and its a nightmare to change the spark plugs... no space to do it, and are 12 spark plugs!

I only tell the true, corvette of 92, EXCELENT CAR!!! OWESOME CAR! But when the car dont ask you to repair, owesome to drive, owesome power, owesome feeling, the people just love the car in the street and respect you because the people know the car has a BIIGGGGG Engine. With mercedes i had an SLK and people dont respect me, everyone thinks that can beat me in a race, with corvette, people just think the oposite good point fot the car.

Bad things about driving? you just CANT SEE WATER!!! My corvette in water is a butter, you see water and you just going to crash.

Another bad thing, a few weeks ago (when the car worked) im just going about 130 miles per hour, and a animal was in the street, i just brake and the car spin out the highway, i almost crash seriously... i have controled the car i dont know why!

With the SLK i brake at 240km per hour in the same situation and the car just brake fine and in straight line.

Another bad things, in corners, the corvette just pull out of the streets... its a car that deserves respect, germans are a lot of faster in corners and has more stability in corners, i look on the internet and i have readed the corvettes sinces 1998 at 2011 are a lot of better in corners, good!!!!

I really love my car, has a unique look, i have spended a lot of money in him with many upgrades like stage 3 Spec Clutch... carbon fiber interior, aluminium bezel on the dash, chip, turbomufflers on the exhaust, etc... Its the only car that i haved that i like to spend money in him in upgrades, i dont know why, but i love it. Clutch i have put the stage 3 because my old clutch was bad, and i just put in the best!

Well... im right now eating some food, a little break, in a few minutes i will go again to the car to check eveything! :eyerole

Hope it works and its worth :eyerole

 

[Bestdavidd]

brothers..... I found the problem!

I just finishing to put a new MSD distributor... new MSD coil... and a new original GM starting module....

and?

guess what happened??????????????

Nothing happened! Same problem... so, i waste at least 600$ more to the trash....

I have checked all the wires, ALL of them, of ALL the car! i found 3 broken wires and i replace it.

The problem is the ECM....a friend of mine here has the same problem after instaling a HYPERTECH chip like me... he tells me that he has the problems before he installed the chip... and one day, like me, the car does not start.

He tells me that he bought a remanufactured ECM (because they doesnt exist new, BAAAAAAAAAD THING TO GENERAL MOTORS....produce cars, but no produce spare parts for the cars... bad one for him) and the problem finished!

I cant test with his ECM because each ECM is programmed for each car and he has sold the car over 6 months ago.

So, whats the best site to buy a remanufactured ECM? because im gonna do it.... And the site that was cheaper, because i have buyed a Mercedes to use daily and im a little bit broken... over 3.000$ are now available to spend in the corvette... and i need new tires (here are AMAZINGLY EXPENSIVE), new windshield glass, i need new paint and other stuff and details...... but now i want to make my car works.

Please help me because im going crazy... i dont like to see my beautiful corvette every day in my garage with a mass of dust and in that conditions... i really love that car, is the seaxiest car i ever had and i want to use it. im not a museum to ´´only see´´...

thanks a lot for the help

 

[vetteoz]

I cant test with his ECM because each ECM is programmed for each car

ECM is not programmed to car in 92 /93
All you do is put the chip out of yours into another same part number ECM ; no different than putting Hypercrap chip in

In any case a chip from a similar C4 LT1 ( man ) will work in any other C4 LT1 man
( A auto chip will also start and run the engine perfectly ; just not calibrated for a man trans )

92 / 93 ECM almost impossible to buy used; $300+ if you can.
Having your rebuilt is usually only option