I'm driving along and all of a sudden just about every light on my dash lit up. I got "reduced engine power", "low tire pressure", "low fuel", "service active handling system", all cycling through my DIC. My dash has the ABS, Traction, CEL, Security and probably a few other lights illuminated. My gas gauge was pegged at E (I have almost a full tank), my oil pressure and oil temp gauges are both showing nothing. My DIC isn't showing any information aside from my battery voltage and the revolving warnings listed above. My radio also shut off which I assume is something having to do with the security system freaking out.

I pulled over, turned off the car, checked for anything drastic under the hood - everything looked fine so I started her back up. Everything is fine all of a sudden, no more codes, no more flashing error messages. Then all of a sudden I'm hit with it all again.

This entire time the car feels perfectly normal, no loss in power, no strange surges, it drives fine. Anyways, I'm hoping someone has run into a similar problem and has some idea what I'm looking at here. I wrote down a list of codes my DIC stored, in all I have about 25 codes. I looked them up and the majority of them point to loss of communication from the IPC, the Tach Signal Circuit, BCM, TCS, just about everything.

I know everything can't break at once so I'm thinking there is some malfunction with the PCM somewhere. Any help?

 

Check your battery - AC Delco 1809's ae infamous for this. Acid seeps out of the postive side female connector. 1997 thru 2000 came from the factory with 1809 on the grey label on top of the battery. If the connector is corroding take the cable end apart by removing the bolt from the cable end and slide the red cover off and clean with arm & hammer. Replace the battery. All of this is just a guess but I've seen it over and over again for 4 years. Good Luck!

 

Lloyd,

I just ran out there and pulled off the battery connections - everything looks clean. I did replace my old AC Delco with a red top Optima a few months back.

Another member suggested I may be looking at the column lock bypass issue.

Keep the ideas coming guys, they're much appreciated.

-Jesse

 

could possibly be a loose cable on your alternator or it's going TU

 

My car just did the same thing coming home tonight. I switched to an Optima at least a year ago. However, I had just been sitting in nasty stop and go traffic and temps were up there.

Have you made any headway? Did the problem come back? I'm heading out in a few to try reconnecting at least the harness plugs I can get to.

Dan

 

Check ground G104. It's the one under the battery box/shroud. It's the stud looking up at you. The PCM is grounded there.

 

Check connectivety from ECM to PCM. and check for corrision around the ECM. Now if you have less than 88000 miles and it's the ECM the dealer will replace it . Check your owners manual.

 

mine did something like that .
even the left headlight went half way up and stopped , and the CD Player in the back started doing all kinds of things.

all it took was a new battery good luck

 

I had the same thing happen to me and it was a bad connection to the Left Door CM. I just cleaned the two plugs between the A-pillar and the door and everything is good.....

 

Hmm, I do have the infamous window seal trickle leak there. Can you be more specific on the location of that connector?

Btw, I cleaned the four front frame grounds last night. The connectors looked fine, with maybe just a little dust on them. No wicked green connectors yet. At least the wire brush and nolox treatment will help.

Seems like I read somewhere that some people were reporting that the engine ground straps were undersized. Something about the ignition curve being smoother with additional ground points added at strategic places. Anyone see that?

Thanks,
Dan

 

You say it was hot... Any sign of A/C condensation drain leakage in the passenger footwell? The BCM is under there and it gets unhappy when it gets wet.

 

Heh - I meant hot as in the radiator fans running constantly. It was cool enough outside that I was not running the a/c and just had a window down.

I'll be pulling the battery tonight and checking out all the connectors in that area. Last night, I did find some white stuff has dripped on one of the header tubes on that side. Will track that down as well.

Thanks,
Dan

 

I had a hard time finding these and hopefully it will be easier for you. I started by removing the “accordion” from the door, but could not find the connectors. I removed the door panel, and still could not find them.

The 2 connectors can be access by removing the “accordion” on the A-pillar side. Pull lightly on the wires and you should see the connectors.

Clean them and make sure they “grab”. Use Bill C’s pull test.

 

I just got mine back from the shop for the 3rd time on this. The second time in they changed the computer in the trunk area. Last week it happened again even with the computer unplugged. They found the wiring harness and connectors in the passenger door was loose and not making full contact. So far so good. I think they found the problem and solved it.

 

All of the things that you mentioned that went spastic, are controlled by the Body Control Module (BCM). It is in the passengers foot well behind the toe board. It can be identified as the big shinny aluminum box. When ever the dash goes crazy, most of the time, it is caused by the BCM. Most of the time, its because it gets wet or damp!! The module is NOT sealed and does NOT like moisture!!!! Been there done that!

This is what I recommend! Whether you do it or not, it's up to you. I would remove the passengers seat and pull up the carpet and see if the jute underlayment is wet/damp. If it is, you need to leave the carpet out, reinstall the seat and look for the leak. If the carpet is wet, let me know and I will give you some recommendations on where to look for the leak.

What year C5 is it and what model is it? (ie coupe, vert or FRC)

Bill

 

It seems to be happening a lot to folks recently. I had the same issue, but only noticed when at Sea Level, versus 5280ft (Denver). Hopefully my problems are fixed.

Michael

 

Hi All,

I just got the same problem, hopefully it is an easy fix with one of these ideas...John