[paul3373]

2000 C5, ran fine past two days. When I try to start it today, it won't even crank. The dash lights come on and give me the following alerts: reduced engine power, check tire pressure sensor, low fuel (even though the gauge shows 3/4), service engine soon.
I don't have a way to get codes from home.
I just replaced the battery, but I do notice corrosive build-up on the + terminal.
Measured 12.2 volts at battery terminals with volt meter
Dash gauge reads battery 11.8 volts
I checked the fuses under the dash
When I went to check the fuses under the dash, I noticed the passenger floor was soaking wet. I did not drive the car in the rain. Could this be from AC?

Any help?

 

[WIT911]

Think your computer has shorted out? :huh:

 

[lil_sleazy1]

Your pcm is fried. This recently happened to me a few weeks ago in Texas during the floods and I have the same exact problems. Is your radio working? I already installed a new pcm but it still wont start for me. I'm getting it towed first thing tomorrow so they can flash it and hopefully it will start. I also had to replace my starter too because it was fried.

If you're looking to save money, order a pcm from your local auto store. Do not take it to the GM to get it flashed because they will charge you double the amount of other auto businesses.

 

[paul3373]

Is there a way to check the PCM before attempting to replace it? I just checked, and the radio does not work. I checked the codes and there are about 15 that come up. I also see:
PCM says NO CODES
40-BCM NO COMM
99-HVAC NO COMM

Assuming I buy a new PCM at a place like Autozone, would they be able to flash it for me as well? Or would I still need to take it to a dealer?

 

[Spiderpat]

Check your Pcm visually. It may have gotten corrosion on it from the Battery. That was a common problem for the early C5's.
Remove the right front tire and the access panel on the rear of the wheel well to gain access to the PCM.
Let us know what you find :thumbsup:

P.S. I don't think that Autozone sells PCM's

 

[The Bad]

Look at this thread about corrosion.:lookinup:

 

[Mike F.]

First of all don't panic. The worst case is about $400 if you have fried the BCM not PCM. Your code 40 BCM is because it is not communicating with your PCM and the rest of the functions it controls. Disconnect the battery when you do the repair. The Body Control Module is located on the passengers side. There is a panel at the end of the floorboard where your feet would rest with two fasteners. Just unsnap the fasteners, pull the panel off and you will see a silver box about 6" X 8". There are 3 plugs to disconnect. You will see how the BCM is mounted, it's not very difficult. It just pops out when you release the holding tab. If your floor is still wet, use a fan or hair dryer to thoroughly dry the area. Take the BCM out and make sure its dry. You may have ruined this unit by getting it wet. The reason it gets wet is usually a clogged A/C drain located on the firewall just behind the passengers side exhaust manifold. Cut the bottom of the drain tube so that it can fully drain. I had to take the circuit board out of my BCM and clean it. I used electrical cleaner and some q-tips. Be careful this is a delicate piece. If that doesn't work you will need a new BCM. They are about $200 from GM Parts Direct. It will cost you about $100 to have Chevrolet program the new unit to your car. It will not start until it has been programmed to your VIN. Good Luck. Mike F. P.S. Do not let anyone except a dealer program this unit. They will need to have the car there to do it. Certainly not Autozone...please.

 

[lil_sleazy1]

First of all don't panic. The worst case is about $400 if you have fried the BCM not PCM. Your code 40 BCM is because it is not communicating with your PCM and the rest of the functions it controls. Disconnect the battery when you do the repair. The Body Control Module is located on the passengers side. There is a panel at the end of the floorboard where your feet would rest with two fasteners. Just unsnap the fasteners, pull the panel off and you will see a silver box about 6" X 8". There are 3 plugs to disconnect. You will see how the BCM is mounted, it's not very difficult. It just pops out when you release the holding tab. If your floor is still wet, use a fan or hair dryer to thoroughly dry the area. Take the BCM out and make sure its dry. You may have ruined this unit by getting it wet. The reason it gets wet is usually a clogged A/C drain located on the firewall just behind the passengers side exhaust manifold. Cut the bottom of the drain tube so that it can fully drain. I had to take the circuit board out of my BCM and clean it. I used electrical cleaner and some q-tips. Be careful this is a delicate piece. If that doesn't work you will need a new BCM. They are about $200 from GM Parts Direct. It will cost you about $100 to have Chevrolet program the new unit to your car. It will not start until it has been programmed to your VIN. Good Luck. Mike F. P.S. Do not let anyone except a dealer program this unit. They will need to have the car there to do it. Certainly not Autozone...please.

I took mine in recently. My BCM was fried along with having to replace many fuses. Grand total - $750 :surprised.