Multiple failures

[Sneakrz]

My ’01 with 60K miles on it has lost its damn mind… I hope someone can help.

I have been dealing with an intermittent security light (I have an aftermarket alarm) and an occasional “active handling warming up” message for a year. The security light typically comes on when I hit a bump (never goes out) and the warm up message normally happens in the first 5 miles and clears after about 10 seconds. After the alarm was installed it seems the unit that accepts the key is loose. I know they had this apart (and of course offer no service after the sale).

During the last 1500 miles of driving I noticed that I have an intermittent problem of the head lights dimming momentarily when I step on the brake and the intensity of the stereo lighting is dependent on the beat of the song I have playing (but not the volume). I notice that when the car does this, the voltage fluctuates as high as 14.2 volts and as low as 11.8 volts with most fluctuations between 12.5 and 13.8 VDC. When the lights do not dim with the brake applications, the voltage is steady at 13.5.

During the last 500 miles I began to get the following messages intermittently but now get them every time I start the car:

Shocks inop
Service Ride Control
Service Vehicle Soon
Service Active Handling
Max speed 80 MPH

The car limits itself to 80 mph (found that out the hard way), the traction control light stays on and the ABS light is often (but not always) illuminated. Trying different settings on the ride control is of no help nor is trying to cycle the traction control.
To top it off, the climate control has totally quit (fuse is OK), the rear view mirror does not have the green light on nor does it dim at night (but the dome light function works ok) and some times I get the courtesy lights when I lock and unlock the car with the factory remote, sometimes I don’t.

I suspected a bad alternator or battery (it has been totally drained at least twice over the last two years) but had them tested at the local auto-parts warehouse and was told they were good.

In a search for answers, I can across your fine website and learned to download my codes. They are:
0-PCM NO CODES
28-TCS NO COMM.
38-RTD NO COMM.
40-BCM
**B0432 Rear Defogger Relay Circuit (wont clear)
B0503 RH DRL Relay Circuit
B0508 LH DRL Relay Circuit
B2483 Backup Lamp Relay Circuit
B2593 unk
B2721 PASS-Key Detection Circuit
**B2723 PASS-Key Detection Circuit (wont clear)
58-SDM
**U1040 H C unk (wont clear)
60-IPC NO CODES
80-RADIO NO CODES
99-HVAC NO COMM.
AO-LDCM
B2282 H Battery #1 Fault
B2284 Battery #2 Fault
U1064 Loss of Communications with BCM
A1-RDCM
B2283 Battery #1 Fault
B2285 Battery #2 Fault
U1064 Loss of Communications with BCM
A6-SCM NO CODES
BO-RFA NO CODES
I attempted to clear the codes and B0432, B2723, and U1040 would not
clear. I started the car (did not drive it) and the codes P1571 ASR
Desired Torque, P1652 Powertrain Induced Chassis Pitch Output Circuit,
and P1689 (unk) came up.
Also when checking the fuel page after the car has not been driven for a week, I get “low fuel”, “low” range and 0 MPG. The main battery had not been discharged significantly as the car started fine.

The fact that I have several “No Comm” messages leads me to believe that I have a bad computer but….

Anyone care to take a stab at the one (or more) of the problems?
Thanks in advance!:bash :W

Jeff

 

[KANE]

My ’01 with 60K miles on it has lost its damn mind… I hope someone can help.

I have been dealing with an intermittent security light (I have an aftermarket alarm) and an occasional “active handling warming up” message for a year. The security light typically comes on when I hit a bump (never goes out) and the warm up message normally happens in the first 5 miles and clears after about 10 seconds. After the alarm was installed it seems the unit that accepts the key is loose. I know they had this apart (and of course offer no service after the sale).

During the last 1500 miles of driving I noticed that I have an intermittent problem of the head lights dimming momentarily when I step on the brake and the intensity of the stereo lighting is dependent on the beat of the song I have playing (but not the volume). I notice that when the car does this, the voltage fluctuates as high as 14.2 volts and as low as 11.8 volts with most fluctuations between 12.5 and 13.8 VDC. When the lights do not dim with the brake applications, the voltage is steady at 13.5.

During the last 500 miles I began to get the following messages intermittently but now get them every time I start the car:

Shocks inop
Service Ride Control
Service Vehicle Soon
Service Active Handling
Max speed 80 MPH

The car limits itself to 80 mph (found that out the hard way), the traction control light stays on and the ABS light is often (but not always) illuminated. Trying different settings on the ride control is of no help nor is trying to cycle the traction control.
To top it off, the climate control has totally quit (fuse is OK), the rear view mirror does not have the green light on nor does it dim at night (but the dome light function works ok) and some times I get the courtesy lights when I lock and unlock the car with the factory remote, sometimes I don’t.

I suspected a bad alternator or battery (it has been totally drained at least twice over the last two years) but had them tested at the local auto-parts warehouse and was told they were good.

In a search for answers, I can across your fine website and learned to download my codes. They are:
0-PCM NO CODES
28-TCS NO COMM.
38-RTD NO COMM.
40-BCM
**B0432 Rear Defogger Relay Circuit (wont clear)
B0503 RH DRL Relay Circuit
B0508 LH DRL Relay Circuit
B2483 Backup Lamp Relay Circuit
B2593 unk
B2721 PASS-Key Detection Circuit
**B2723 PASS-Key Detection Circuit (wont clear)
58-SDM
**U1040 H C unk (wont clear)
60-IPC NO CODES
80-RADIO NO CODES
99-HVAC NO COMM.
AO-LDCM
B2282 H Battery #1 Fault
B2284 Battery #2 Fault
U1064 Loss of Communications with BCM
A1-RDCM
B2283 Battery #1 Fault
B2285 Battery #2 Fault
U1064 Loss of Communications with BCM
A6-SCM NO CODES
BO-RFA NO CODES
I attempted to clear the codes and B0432, B2723, and U1040 would not
clear. I started the car (did not drive it) and the codes P1571 ASR
Desired Torque, P1652 Powertrain Induced Chassis Pitch Output Circuit,
and P1689 (unk) came up.
Also when checking the fuel page after the car has not been driven for a week, I get “low fuel”, “low” range and 0 MPG. The main battery had not been discharged significantly as the car started fine.

The fact that I have several “No Comm” messages leads me to believe that I have a bad computer but….

Anyone care to take a stab at the one (or more) of the problems?
Thanks in advance!:bash :W

Jeff

Ouch.

Yeah, have the memory wiped. I sounds like you could have a bad ECM. If for no other reason you'll have a new baseline.

FYI- the low fuel thing is usually due to a dirty sensor. Try Techron from Chevron- folks here on the CAC swear by it.

 

[67HEAVEN]

Jeff,

I've moved your thread to the C5 section (from C7) where it should get more response.

Welcome to the

 

[gmjunkie]

Disconnect Battery and CLEAN ALL Grounds!! By Lt and Rt Hood hinge on frame, Under Battery on frame,Under Power brake Booster on frame,Behind Lt rear wheel on frame,And Both Battery cables!!! This may Fix it!!! If not, it will fix part of it I'm sure!!
PS Also Load Test Battery,a weak cell can cause all sorts of Havoc with the ECM!! Charging a Low or Dead Battery while still connected to the car,Can Scramble it's Brain!! And a reboot of the ECM can take care of it!!

WELCOME to

 

[DRTH VTR]

I would think that a proper diagnosis in a reputable shop is the way to go. It would be cheaper than randomly throwing new parts on it. The Corvette does NOT currently have the safety features that were designed into the car. I had to have the ABS/traction control computer module replaced once. I could not have diagnosed or replaced that myself.

By the way, I was born in Bartlesville.

Welcome to the CAC!

 

[XLR8]

Welcome Jeff. Sorry to hear you're having issues with your Vette. Hope you get them straightened out soon.

Jane Ann

 

[DanHammer]

Been there and done that.

I had similar problems you described about a couple of years back. During the day, I did not really noticed the problem, except it would throw some weird codes you described ... like the traction control. At night, I had the same problem of the head lights flickers and dimming out. Other times just stepping on the brake, the dash panels lights also dims or flickers, during the day or night.

I had it serviced ... they replaced the serpentine belt and battery. After a week, I still had the same problem with the headlights and dash panel lights dimming or flickering. Finally, they replaced my alternator ... that seemed to have resolved all my problem. I have not had any codes since then and been really on a smooth sailing.

But I suspect that it was a combination of having a weak battery and the alternator working overtime most of the time. I hope this helps you out ... the C5 just have too many electonics that when the battery gets weak, weird codes start to come out. I been there and done that!!! Good Luck and hope your baby gets fixed soon.

save the wave ... Dan

 

[wishuwerehere82]

Do what Gmjunkie suggested. It sounds like a weak battery or connections.

 

[c5y2k]

I agree with GMJunkie also. The grounds in the C5 are notorious for getting corroded. They are also pretty easy to check and will only cost you time in looking.

You might want to check ECM to make sure the battery hasn't leaked acid down on it. It sounds like you have been in the fuse box already, did you notice any water damage? I'm not sure if you run the A/C much but its a common issue for the A/C drain to get plugged and fill the fuse box area with water.

 

[Sneakrz]

Thanks for all the info and the warm welcome.

4 Grounds under the hood looked good but I lightly touched them up with a non-metallic scrubber pad and contact cleaner.
No evidence of battery acid but I accessed the two boxes below the battery and cleaned the connections.

No evidence of water backup or moisture build up under the floor or in the AC system.

I had the battery retested and 2 out of 4 places said it was bad so I replaced it.

Have an appt with the MIB to get the memory flashed.

I am still getting most of the codes back and I cannot solve the "no comm" problems with the TCH HVAC and RDT.
What do these items have in common?
Where are the computer located?

I will be checking both the doors' wiring (found this info on a different site) as apparently that has been causing some similar problems on C5's.

Thanks again and if anyone has any more ideas, let me know...
Jeff

PS I found a couple of great sites if you are new to wrenching on your vette that pertain to this thread. I hope this is appropriate.
Cleaning of the grounds...http://forums.corvetteforum.com/showthread.php?t=896875
Information about fixing every little gripe I have had with my C5 http://www.southerncarparts.com/info_pages.php?pages_id=14

 

[Sneakrz]

Well you will be glad to know we have an apparent end to this thread... I hope...

I pulled the RDT module in the rear of the car and it looked fine. Plugged it back in at noticed the HAVC working. Weird...
Cleared the codes and started it. No TCS or ABS messages.... OK...

Well to make a long and frustrating story short, about 4 inched down the wiring harness I found where several wires were worn to the conductor. I dont know if it was installed this way or happened from someone else R&Ring the box in the past but it seems to have fixed the problem.

I have some longer trips to take here in the next several weeks and we'll see if it holds up.

Thanks again for all your help!!!!!
Jeff

 

[MsSchroder]

Good job. Here's hoping that's the end of the problems!