Help! ELECTRICAL NIGHTMARE 2001 Chevrolet Corvette 5.9L

[Tonymarine]

Hello

To say my car is in trouble is an understatement. It’s been to 2 different mechanics with no solutions.

It appears to have to have many electrical issues. While driving the vehicle, the instrument panel will light up with “reduced engine power” gauges will go to zero, fuel, gas etc. Radio cuts off, AC stops working (still blows air, just not cold).

Once you turn the car off and turn it back on everything works again. Sometimes for 5 minutes, sometimes for an hour. I have reset the codes and they all come back.

Right now there are 58 codes that show up, most of them deal with a lack of communication.

Now to make things better the battery dies if it’s not disconnected when you stop driving the car for any length of time. Obviously there is some kind of drain on the battery. I did notice that the air conditioning button, which controls the fan speed, has a light behind it that does not go out regardless of whether the AC is on or not. I am assuming this is what is draining the battery.

Here are the codes:

1. 10 - PCM (Powertrain Control Module)
(P1626H) Theft Deterrent Fuel Enable Signal Lost


2. 28 - TCS (Traction Control System)
(U1301H) Class 2 Short to Battery
(C1226H) Wheel Speed Sensor Circuit
(C1293H) Master Cylinder Pressure Sensor Circuit
(U1000H) U1000 and U1255 Class 2 Communication Malfunction


3. 40 - BCM (Body Control Module)
(U1255H) ECU Malfunction
(U1096H) U1000 and U1255 Class 2 Communication Malfunction
(U1016H) U1000 and U1255 Class 2 Communication Malfunction
(U1255H) U1000 and U1255 Class 2 Communication Malfunction
(B2527) Horn Relay Circuit
(B2593) Column Lock/Unlock Drive B
(B2721) PASS-Key Detection Circuit
(B2723) PASS-Key Detection Circuit

4. 58 – SDM
(U1000H) U1000 and U1255 Class 2 Communication Malfunction
(U1301H) Class 2 Short to Battery
(U1096H) U1000 and U1255 Class 2 Communication Malfunction
(U1064H) U1000 and U1255 Class 2 Communication Malfunction


5. 60 - IPC (Instrument Panel Cluster)
(U1255H) U1000 and U1255 Class 2 Communication Malfunction
(U1064H) U1000 and U1255 Class 2 Communication Malfunction
(U1016H) U1000 and U1255 Class 2 Communication Malfunction
(U1040H) U1000 and U1255 Class 2 Communication Malfunction
(U1080H) U1000 and U1255 Class 2 Communication Malfunction
(U1176H) U1000 and U1255 Class 2 Communication Malfunction
(U1160H) U1000 and U1255 Class 2 Communication Malfunction
(U1088H) Class 2 Communication Malfunction

7. 80 – Radio
(U1064H) U1000 and U1255 Class 2 Communication Malfunction
(U1016H) U1000 and U1255 Class 2 Communication Malfunction
(U1096H) U1000 and U1255 Class 2 Communication Malfunction

8. 99 - HVAC (Heater Vent-Air Conditioning)
(U1064H) U1000 and U1255 Class 2 Communication Malfunction
(U1060H C) U1000 and U1255 Class 2 Communication Malfunction
(U1096H) U1000 and U1255 Class 2 Communication Malfunction
(U1255H) U1000 and U1255 Class 2 Communication Malfunction

9. A0 - LDCM (Left Door Control Module)
NO Communications

10. A1 - RDCM (Right Door Control Module)
(U1064H) U1000 and U1255 Class 2 Communication Malfunction
(U1016H) U1000 and U1255 Class 2 Communication Malfunction
(U1096H) U1000 and U1255 Class 2 Communication Malfunction
(U1255H) U1000 and U1255 Class 2 Communication Malfunction
(B2283) B2282-B2285 Battery Supply Voltage Circuit
(B2285) B2282-B2285 Battery Supply Voltage Circuit



11. AC - SCM (Seat Control Module)
(B0851) Battery 1 Out of Range
(U1255H) U1000 and U1255 Class 2 Communication Malfunction
(U1060H) U1000 and U1255 Class 2 Communication Malfunction
(U1016H) U1000 and U1255 Class 2 Communication Malfunction
(U1064H) U1000 and U1255 Class 2 Communication Malfunction
(U1300H) Class 2 Short to Ground


12. B0 - RFA (Remote Function Actuation)
(U1000H) U1000 and U1255 Class 2 Communication Malfunction
(U1255H) U1000 and U1255 Class 2 Communication Malfunction
(U1016H) U1000 and U1255 Class 2 Communication Malfunction
(U1064H) U1000 and U1255 Class 2 Communication Malfunction
(U1096H) U1000 and U1255 Class 2 Communication Malfunction
(C2100H)
(C2105H)
(C2110H)
(C2115H)

13. A6 – SCM
(B0851) Battery 1 Out of Range
(U1300H) Class 2 Short to Ground
(U1255H) U1000 and U1255 Class 2 Communication Malfunction
(U1016H) U1000 and U1255 Class 2 Communication Malfunction
(U1064H) U1000 and U1255 Class 2 Communication Malfunction

I am not sure at this point if there is a fix, other than detonating the car in place, but any assistance would be greatly appreciated.

 

[Hib Halverson]

Without seeing this car myself, I can't offer any concrete solutions, however, that you have so many DTCs relating to Class 2, the first place I'd start looking for problems is chassis grounds and the connections between all the cars processors.

Also, you really don't need a "mechanic" you need a technician who has experience with C5 Corvette diagnostics.

What is the condition of the battery and the battery connections?

Lastly, the subject field says "Corvette 5.9L" but no C5 has a 5.9L engine. Any chance this car is modified?

 

[Tonymarine]

Without seeing this car myself, I can't offer any concrete solutions, however, that you have so many DTCs relating to Class 2, the first place I'd start looking for problems is chassis grounds and the connections between all the cars processors.

Also, you really don't need a "mechanic" you need a technician who has experience with C5 Corvette diagnostics.

What is the condition of the battery and the battery connections?

Lastly, the subject field says "Corvette 5.9L" but no C5 has a 5.9L engine. Any chance this car is modified?

First off, that you for responding. I seriously doubt the car has been modified, the 5.9L is probably just related to my own ignorance. I looked on the advanced auto site, its probably a 5.7L. The battery is less than a year old and seem to be in great condition, the connections are new and clean. Right now, due to the problem with the battery draining I have put in a "throw switch" for lack of a better term that I purchased at advanced auto which allows for easy disconnect of the battery without having to unscrew the terminal all the time.

Is there a place I can do to get a diagram of where all of the ground wires connect to, as well as the connection between the processors or do you think that would be a serious undertaking that should only be done by professionals?

 

[kpic]

Before you go fixing the hard stuff; try something easy. A trickle charger or battery maintainer instead of taking the battery off line. My C5 does not like lacking a battery or a dead battery.

 

[Tonymarine]

Before you go fixing the hard stuff; try something easy. A trickle charger or battery maintainer instead of taking the battery off line. My C5 does not like lacking a battery or a dead battery.

Mr Kpic

I understand the concept of what you are saying but the battery is just the latest issue in a long line of problems. It started about 2 weeks ago. The other problems have been going on for months.

My concern with the trickle charger is that the battery would be in a constant state of push/pull. Always discharging from an internal source due to the draw from the light and possibly some other source I don't know about and charging from the external source, ie the trickle charger.

 

[DSterling]

Here is the fix for you (I hope)

I know what the problem is!!!!

I have a 2002 convertible and had the same problem a few months ago. Here is what it turned out to be.
Whenever it was going to happen the driver door control panel (windows, mirror, seat, etc.) went dead. Did this happen with you??? It lost all power to its lights and ability to control anything including the windows. I went looking for a short someplace assuming the short would cause a hit to the main computer as there are data lines going through there. After removing the door panel I found no problems in the door. Than I went to the wire loom going to the car through the corrugated rubber boot. I had found a comment further down on this list about a short in the wires going through the door pillar. After a complete maticuls check I found nothing, BUT as I was pulling things around I got the "lite turn off" in the door control panel (the prerequest to a flashing lites binge). After much wiggling of individual wires going through the plugs with a schematic in front of me (I have the full set of service manuals) I found the plug blade (just the one individual wire) feeding the power to the panel to be intermittently not connecting. It seemed clean but it must have had some sort of corrosion on it.

After much cleaning of the male and female part of the plug (including electrical point cleaner spray and fine small crocus cloth strips) and the addition of terminal spray lube plus slightly bending the spring part of the female for a tighter fit, I managed to get a reliable connection.

PROBLEM SOLVED. I have not had the problem for the last 3 months!!!!!!!

Let me know how you make out - Good luck. Doug

 

[Tonymarine]

I know what the problem is!!!!

I have a 2002 convertible and had the same problem a few months ago. Here is what it turned out to be.
Whenever it was going to happen the driver door control panel (windows, mirror, seat, etc.) went dead. Did this happen with you??? It lost all power to its lights and ability to control anything including the windows. I went looking for a short someplace assuming the short would cause a hit to the main computer as there are data lines going through there. After removing the door panel I found no problems in the door. Than I went to the wire loom going to the car through the corrugated rubber boot. I had found a comment further down on this list about a short in the wires going through the door pillar. After a complete maticuls check I found nothing, BUT as I was pulling things around I got the "lite turn off" in the door control panel (the prerequest to a flashing lites binge). After much wiggling of individual wires going through the plugs with a schematic in front of me (I have the full set of service manuals) I found the plug blade (just the one individual wire) feeding the power to the panel to be intermittently not connecting. It seemed clean but it must have had some sort of corrosion on it.

After much cleaning of the male and female part of the plug (including electrical point cleaner spray and fine small crocus cloth strips) and the addition of terminal spray lube plus slightly bending the spring part of the female for a tighter fit, I managed to get a reliable connection.

PROBLEM SOLVED. I have not had the problem for the last 3 months!!!!!!!

Let me know how you make out - Good luck. Doug

Hello Mr Doug

Funny you should mention that friggen door, you are correct in that the drivers side door, window, mirror and controls to not work! That was the initial start of this adventure along with visits to 3 mechanics with no resolution to the problem.

While I can admit I am not Mr. Automechanic I do most of the maint on my vehicles, within reason. You have given a very detailed description of where the problem should be at, but I will admit I would be remiss if I did not say I am a little confused at where this bundle is. Are we talking about where the door hinges to the vehicle? These are the statements that are a bit confusing, I am sure its probably clear to everyone else "I got the "lite turn off" in the door control panel (the prerequest to a flashing lites binge). "I found the plug blade (just the one individual wire) feeding the power to the panel to be intermittently not connecting."

Any additional correspondence would be greatly appreciated.

Respectfully,
Tony Davidson

 

[DSterling]

Clarification of Solution

I know what you mean. Sometimes it is confusing when your not actually looking at it.

Here we go:

"I will admit I would be remiss if I did not say I am a little confused at where this bundle is. Are we talking about where the door hinges to the vehicle?"

Yes. The wires go through a corrugated rubber connector boot between the door and the door pillar on the body. It is a little tight in there, but it can be worked with (I made out OK). The boot can be pulled out of ether end and worked back in somewhat easily with a screw driver. You can release the corrugated rubber boot at the pillar and pull the wires into the area between the open door and the pillar (just squeeze it and pull it off the pillar). You now can pull the 2 connectors out of the pillar (there is a loop of slack in there). Now if I remember correctly the power feed wire is the larger orange colored wire. If you are in a semi dark garage and can turn on the low lights and wiggle this wire. If you are lucky the lights on the door panel switches will blink on and off.

Remember to hold the connector lock open when pulling it apart to clean or you might break something. Use contact cleaner and lube (I get mine at Radio Shack) and maybe a little fine sanding paper (you might want to disconnect the battery while you are sticking things into the connectors). I'd clean all the points while I was at it. Also check out the condition of the loom as another person did this and found a rubbed through short that he had to tape up. This might be your dead battery problem combined with the power to the module problem. Mine was clean of rub marks and OK. Replug the plugs, reconnect the battery, and check for operation before you stuff everything back in, than check it again after you stuff the wires back into the pillar.

The give away is in the code dump you did:

9. A0 - LDCM (Left Door Control Module) NO Communications

It would seem to indicate a power loss to the module or a short out, and you said that you had lost power to all the door switch functions (the job of the control module).

I removed the door panel to check out all the wiring in the door, but found no faults there. Maybe you will be lucky and not have to do that (It was a pain).

BTW - Whenever I had the "fault cascade" I would stop, turn off the car, open the door and wiggle and squeeze the corrugated boot and the door panel lights would go back on and everything would work fine for a while just like your turn off and restart experience.

You might want to get the service manuals (if you are going to keep the car) as they were invaluable to me for identifying electrical things and disassembling various components.

I did control wiring installation and repair for big central supermarket refrigeration systems before I retired so I am somewhat used to this type of troubleshooting.
Let me know how you make out and Good luck, Doug


9. A0 - LDCM (Left Door Control Module)
NO Communications
- See more at: http://www.corvetteactioncenter.com...rolet-corvette-5-9l.html#sthash.CBcOLa91.dpuf

9. A0 - LDCM (Left Door Control Module)
NO Communications
- See more at: http://www.corvetteactioncenter.com...rolet-corvette-5-9l.html#sthash.CBcOLa91.dpuf

9. A0 - LDCM (Left Door Control Module)
NO Communications
- See more at: http://www.corvetteactioncenter.com...rolet-corvette-5-9l.html#sthash.CBcOLa91.dpuf

 

[Tonymarine]

I know what you mean. Sometimes it is confusing when your not actually looking at it.

Here we go:

"I will admit I would be remiss if I did not say I am a little confused at where this bundle is. Are we talking about where the door hinges to the vehicle?"

Yes. The wires go through a corrugated rubber connector boot between the door and the door pillar on the body. It is a little tight in there, but it can be worked with (I made out OK). The boot can be pulled out of ether end and worked back in somewhat easily with a screw driver. You can release the corrugated rubber boot at the pillar and pull the wires into the area between the open door and the pillar (just squeeze it and pull it off the pillar). You now can pull the 2 connectors out of the pillar (there is a loop of slack in there). Now if I remember correctly the power feed wire is the larger orange colored wire. If you are in a semi dark garage and can turn on the low lights and wiggle this wire. If you are lucky the lights on the door panel switches will blink on and off.

Remember to hold the connector lock open when pulling it apart to clean or you might break something. Use contact cleaner and lube (I get mine at Radio Shack) and maybe a little fine sanding paper (you might want to disconnect the battery while you are sticking things into the connectors). I'd clean all the points while I was at it. Also check out the condition of the loom as another person did this and found a rubbed through short that he had to tape up. This might be your dead battery problem combined with the power to the module problem. Mine was clean of rub marks and OK. Replug the plugs, reconnect the battery, and check for operation before you stuff everything back in, than check it again after you stuff the wires back into the pillar.

The give away is in the code dump you did:

9. A0 - LDCM (Left Door Control Module) NO Communications

It would seem to indicate a power loss to the module or a short out, and you said that you had lost power to all the door switch functions (the job of the control module).

I removed the door panel to check out all the wiring in the door, but found no faults there. Maybe you will be lucky and not have to do that (It was a pain).

BTW - Whenever I had the "fault cascade" I would stop, turn off the car, open the door and wiggle and squeeze the corrugated boot and the door panel lights would go back on and everything would work fine for a while just like your turn off and restart experience.

You might want to get the service manuals (if you are going to keep the car) as they were invaluable to me for identifying electrical things and disassembling various components.

I did control wiring installation and repair for big central supermarket refrigeration systems before I retired so I am somewhat used to this type of troubleshooting.
Let me know how you make out and Good luck, Doug


9. A0 - LDCM (Left Door Control Module)
NO Communications
- See more at: http://www.corvetteactioncenter.com...rolet-corvette-5-9l.html#sthash.CBcOLa91.dpuf

9. A0 - LDCM (Left Door Control Module)
NO Communications
- See more at: http://www.corvetteactioncenter.com...rolet-corvette-5-9l.html#sthash.CBcOLa91.dpuf

9. A0 - LDCM (Left Door Control Module)
NO Communications
- See more at: http://www.corvetteactioncenter.com...rolet-corvette-5-9l.html#sthash.CBcOLa91.dpuf

Mr Doug,

Thanks very much. I will keep you posted. I actually pulled the boot back tonight when I met my wife for dinner and you are not kidding, its tight. Thanks for the clarification and about the fact that there is some slack in there. I will get the contact cleaner tomorrow and take a look this weekend. Again, very much appreciated!

Respectfully,
Tony Davidson

 

[Hib Halverson]

If you are going to diagnose/repair your car's electrics yourself, buy a set of Service Manuals. CAC sponsor Zip Products sells them.

Once you get them, you'll have wiring diagrams, component locators and removal/repair instructions for virtually all the electrical components in the car.

One reason the battery keeps going dead might be the short(s) you have in the car's Class 2 system which are identified by two of the codes which are set:
U1300
U1301

Get the FSM then start the diagnostic work on those to fault codes. Once you fix the shorts, charge the battery then have it tested. It's possible successive deep cycles have "killed" the battery. If that's the case, replace the battery, clear codes and road test.

Note that all those DTCs except U1060 were history codes which means they have occurred in the past but were not occurring at the time modules were commanded to send data. The U1060 was both a history code and a current code which means, the code had been present in the past and was occurring at the time you "pulled" codes.

In any event, that so many Class 2 codes are set is a clue that something is amiss in the cars Class 2 communications network.

 

[DSterling]

That is an interesting thought

The fault be it a short or a disconnected wire seems to cause a multiple fault to be indicated to the main computer. That is why all the fault lights go off at the same time (Lo oil, lo fuel, traction control, basically everything on the instrument panel). There are data lines running through that loom to the door.

I don't know why on my car the disconnect of the power to the door module would cause such a scramble of fault lights?? Basically the same that he has with his car. Every time the fault stopped - the codes would be marked as history so they wouldn't be thought as happening now. I don't know what the logic built into the computer's firmware is but it doesn't seem to make sense that a single fault would cause the cascade of fault indications that seems to be happening?? I don't believe that anyone believes that all the faults that are indicated are actually happening. It just seems to be a screw up in the computer caused by one fault or one data line. That is what seemed to happen with mine a few months ago with the disconnect, and now his. There is another thread happening like this one a few months ago in this listing, and I remember seeing one a few years ago that resolved itself with a rubbed through loom to the drivers door.

We'll see how the outcome of his search this weekend comes out.

 

[Tonymarine]

If you are going to diagnose/repair your car's electrics yourself, buy a set of Service Manuals. CAC sponsor Zip Products sells them.

Once you get them, you'll have wiring diagrams, component locators and removal/repair instructions for virtually all the electrical components in the car.

One reason the battery keeps going dead might be the short(s) you have in the car's Class 2 system which are identified by two of the codes which are set:
U1300
U1301

Get the FSM then start the diagnostic work on those to fault codes. Once you fix the shorts, charge the battery then have it tested. It's possible successive deep cycles have "killed" the battery. If that's the case, replace the battery, clear codes and road test.

Note that all those DTCs except U1060 were history codes which means they have occurred in the past but were not occurring at the time modules were commanded to send data. The U1060 was both a history code and a current code which means, the code had been present in the past and was occurring at the time you "pulled" codes.

In any event, that so many Class 2 codes are set is a clue that something is amiss in the cars Class 2 communications network.

Mr Halverson

I have been doing numerous searches for manuals without success. You mention this CAC products, I tried doing a search for that and I was not successful. Could I ask you to either provide a like or maybe spell out what CAC means so I can have better luck with obtaining these diagrams.

Again, all of the assistance is greatly appreciated.

Respectfully,
Tony Davidson
l

 

[DSterling]

Manuals

I got my set from West Coast Corvettes a few years ago.

 

[BigJimZ16]

​CAC = Corvette Action Center, the forum you are logged into... Zip Products is a vendor who sells Corvette stuff, they are a sponsor of this site!

http://www.zip-products.com

 

[Hib Halverson]

Mr Halverson

I have been doing numerous searches for manuals without success. You mention this CAC products, I tried doing a search for that and I was not successful. Could I ask you to either provide a like or maybe spell out what CAC means so I can have better luck with obtaining these diagrams.

Again, all of the assistance is greatly appreciated.

Respectfully,
Tony Davidson
l

Ah...click on this link.

 

[Tonymarine]

Mr Doug,

Thanks very much. I will keep you posted. I actually pulled the boot back tonight when I met my wife for dinner and you are not kidding, its tight. Thanks for the clarification and about the fact that there is some slack in there. I will get the contact cleaner tomorrow and take a look this weekend. Again, very much appreciated!

Respectfully,
Tony Davidson

I wanted to report on my progress thus far. While I remain hopeful, so far things seem to be going good. I did as you suggested and got the cleaner. I took apart the connectors and both of them were coated with a film of oxidation, probably due to living near the beach. Not sure if the pics do justice to the amount corrosion on the prongs. I put the cleaner on, did some work on them, cleaned them some more and put them back together and let it sit for about an hour to dry.

My first test drive and so far so good. All the door controls worked, which have not worked in about 6 months and the car, which usually never made it out of the neighborhood without the dash lighting up like a Christmas tree remained silent. I also cleared all the codes before the 5 mile drive and no codes where there when I returned. Turned signals don't work but hey, one step at a time

I will drive the car this weekend and see how things go. Thanks for all your help and suggestion so far

 

[Otter]

Crossing my fingers for ya.