I have read and read and searched and read some more...but I don't have an answer. Maybe that is because I need to have her take it in...

Here we go...She has a '97 Coupe, Auto, with about 61K on it. The P.O. had a battery leakage issue or something, as the dealership had to replace the computer and the wiring harness (?). Recently, for no apparent reason, everything has been going off, starting with traction control, then all the gauges start going haywire...I checked the fuses, ok, I checked the grounds (quickly), seemed ok, She is going to take it down and have the battery tested tomorrow (don't know how old it is). I told her that from what I could figure out on here, when A LOT of stuff starts going haywire at the same time, that is/could be a sign of a battery going south. Is that true??? I also told her that the next time it happens to pull the codes (showed her how) and write them down. I have disconnected the battery, cleared the codes, cleared them again....

here are the codes as it was happening tonight, she didn't turn off the car, just pulled the codes and called...

10PCM
-p1571 H
-p1626 H C

28TCS
-u1301 C
-u1016 C

38RTD - NO COMM

40 BCM
-u1040 H C
-u1016 H C
-u1096 H C
-u1255 H

60IPC
-u1040 H
-u1016 H
-u1255 H
-u1064 H
-u1176 H

80RADIO
-u1016 H
-u1064 H

99HVAC
-u1064 H
-u1096 H
-u1160 H
-u1255 H

A0-LDCM
-u1064 H

A1-RDCM
-u1064 H

A6-SCM
-B0856 H
-u1255 H

B0-RFA
-u1255 H
-u1096 H
-u1016 H

I have read on here that the "U" codes are really no big deal, but doesn't that seem like a BUNCH?!?!!?

OK, so ANY help would be appreciated. Point me in the right direction of what to check, where, and how. I will post up how the battery test turns out, and I will check on here regularly as I am on Christmas Break (one of the perks of teaching). Thanks in advance.

Jason

 

SORRY,,,,,,,,,,,,,,,THE CAR IS TRASHED! Ill be right over to take it off your hands.

On a more serious note, you most likely have a wet BCM computer. Look in the passengers foot well behind the toe board where the fuse box is located.






This is the Body Control Module:



If the module get damp or wet,,,you will have these issues! Been there!

You will need to throughly examine the passengers foot well for water intrusion. The carpet under layment will be the tell tail evidence as it takes a LONG time to dry once it is wet.

Check the jute under layment in as many areas as you can. If it is wet. let me know and I will provide more info to fix it.

You can clear ALL the codes and everything will most likely return to normal.

BC

 

OK, I will check that tomorrow after they check the battery. Thanks Bill.

Jason

 

I feel for your mother; intermittent wiring / electrical issues of this kind are no fun at all.

Being a skeptic, I would want some proof that the dealer actually replaced any wiring, rather than simply cleaning it up (poorly done?). The leaking battery issue is a well documented one; basically the stock GM side-post terminal batteries used in the C5 were prone to leak acid out of the terminal areas, and unfortunately the PCM and lots important wiring sits directly in the path.

These issues could stem from the defective battery event, they could be from poor grounds (do a search for Bill C.'s posts on the subject, stickies at the top of this forum) or defective battery terminal connections / another defective battery (if the car is not driven often, battery life will suffer).

Above all, good luck!

 

When your in there checking the battery, check the one terminal post
next to the underhood fuse box! One of the battery cables is looked up
to it. Make sure that it is on tight. Worth a look. My 2000 c5 was having
similar electrical issues ( gauges resetting on and off and turning off and on). Like you I was thinking battery so I took a look and found that terminal on finger tight! No more issues. Good luck, Tom

 

Battery checked out OK. No wet anywhere on the floor. Cleared codes and as soon as I started the car 10PCM came back with a P1571 H (ASR Desired Torque). What does this mean????


HELP????

Thanks

Jason

 

don'y worry about the 1571 because that code is almost always in the 97s. Mine has had that since I have owned it. I can clear it and as soon as I start it it's back

 

Reference to teh P1571 code
http://forums.corvetteforum.com/show...Desired+Torque


Stated from Bill Curlee past post.


97 and early 98 C5's have "REAR" mounted EBTCMs Late 98-2004 C5's have front mounted EBTCM's For us to properly lead you through the repair, you will need to indicate which one you have! If you see a module on the back of your differential that has a large connector and lots of brake lines attached to it; you have a rear mounted EBTCM.

If you have a module in front of the alternator and between the radiator and the engine on the drivers side, you have a front mounted EBTCM.


Check your BCM in the passengers foot well for moisture. A good indication of a WET BCM will be tons of warning lights that don't really indicate that there really is an issue. I had every warning possible but the car ran FINE! The water will come from a clogged HVAC Air Box drain or a leak from 3-4 areas.

You CAN clear codes by disconnecting the battery! It will clear EVERYTHING! Even your BCM temp memory. Sometimes when you hook the battery back up, it will set a code if it isn't a good clean "quick" hook up.


BC

 

You have or had a wet BCM. Disconnect the battery, pull and disconnect the BCM and set it some where warm and dry. On top of a living room lamp worked nicely. When you reconnect the battery, most of the time it sets DTC Codes. It normal.

Are you sure that you checked UNDER THE CARPET? The area directly under the passengers seat is where the water runs to. Once that JUTE UNDERLAYMENT gets wet, its tough to dry while its in the car.Give that a recheck/

BC

 

Just one more thing to check before you start spending money. I have seen this on two cars. Both with the same issues you have stated but they also had problems with the driver door controls while it was happening. Both turned out to be the ground wire shorting in the wire bundle between the drivers door and the car. Pull the rubber boot out and inspect the wires. If the connectors have any exposed wire simply tape it up.

 

Yep

seen that cause issues too. Here is what the connector looks like and an examplw of the BAD wire:





BC

 

Well I THOUGHT I checked it good...here is what I did:
Pulled the toe cover, all looked dry, pulled the carpet back a little, all looked dry, stuck my hand up under the carpet as far as I could, I felt nothing. So if I didn't check it good enough, how should I go about pulling the carpet back without screwing it up??? Do I need to take the door sill off??

As for removing the BCM...in your picture above, the BCM is the shiny box, right?? How exactly do I get it off?? Do I pull the plugs first?? When I pull the plugs on the left, is there anything I should be aware of (Careful of)? How long do I leave it on the lamp?? Would it be better next to a fireplace (Not too close)??

Sorry if I sound ignorant, but I don't want to screw up Mom's car. I would LOVE to help her and be able to clear up the codes...

Thanks for the help.

Jason

 

If you move the seat alll the way forward you can lift the carpet on the bulkhead behind the seat, After you do that, you chould be able to feel the underlayment under the seat area. If it dry after that, forget that theory

he BCM is the aluminum box to the left of the fuse box. Remove the battery negative cable first. Then pull down on the tab on the BCM and lift it out. It is NOT bolted in.
Once it is out, you can remove the connections. Anyplace warm and dry should do fine. I left mine to dru for 4-5 hours.

 

OK...my Mom is coming in to town later today. I told her to bring the car and swap with me...I will then double check the carpet...I will also pull the BCM and dry it inside tonight.

I also want to check out the door wiring...how hard is it to pull the tunnel?? Do I just keep pulling on it??

Talking to her, she said that it happened yesterday while she was doing a U-turn to pull it into the driveway...Don't know if that is a clue or not....

I will update with anything that I find (Or don't).

Jason

 

So I rechecked the carpet behind the seat...not wet. Took it for a nice long drive...no codes except the P1571 H. As soon as I turn the car off and restart. When she dropped it off, I noticed that there was a code B0846 H ...

The mechanic tested the battery under load and said it was good. However on my drive I was watching the batttery charge gauge and it ran at 14.5 for MOST of the drive...only dropping to 14 a few times while at stop lights. Is that a normal level??? Seems high to me, but what do I know....