wldstrk98

Hi,

Sorry - this post is rather long, but before I get to the "issues" - 2 disclaimers:

1 - I read through the sticky on electrical issues - will certainly help with various odd codes and "glitches" but I need a little more specific info.

2 - I know I brought this on myself by a) taking my dog for a ride in the car and b) waiting far too long to address the damage in the first place. So please don't beat me up too bad.

Background: I had to take Tigger, my rottie, to the vet - it's only a 15 min ride so no prob, I'll take the Vette. On the way home I stopped and got a flavored mocha and put it in the cup holder (modified to actually hold stuff). Tigger is rather large so getting him in/out of the car involves a bit of maneuvering. During the process of getting him out he squashed the cup with the mocha between his hind end and the heater control unit... about 1/3 of the mocha ended up all over the heater control unit, ashtray/lighter area, in the shift boot, floor... etc. I cleaned it up immediately but the liquid had gotten into the front of the heater control unit. The buttons were hard to push but everything worked. After a while most of the buttons quit lighting up but it still worked so I put off replacing it - too many other things to worry about.

Last week I turned on the rear defrost and heard "clicking" noises and noticed that the headlights and dash lights blinked as well. I turned off the rear defrost and all seemed to be well.. until my fiance turned up the heat on his (passenger) side .. the heater went nutz - the heat was blowing full blast, the front defrost was turning its self on and off and we couldn't turn it off. Fortunately we were still in front of the house so I put it back in the garage.

The following day the battery was dead. I removed the fuses for the HVAC and A/C and we charged the battery. I started it up and took it out for a short drive - ran fine. There were a couple error messages, tire pressure sensor errors, service engine soon msg, and a couple other msgs. but it ran fine. When I got home I disconnected the battery - just in case. I contacted the gentleman that sells the units via Ebay and bought a replacement.

I got the replacement heater control unit and spent a long time replacing it last night (next time I'll remove the stick shift instead of trying to work around it). I checked/cleaned the area below the heater control unit and it looks like the coffee was confined to about a 4" x 4" area under the control unit. Other than being sticky, the wiring looks fine. I cleaned the connections with electrical cleaner before plugging them into the new unit. Today I reconnected the battery, no codes and the heater worked so we took it out for a drive.

We went to our favorite burger joint, grabbed some food and sat in the car watching the tunerz drive by - Here's what happened:

The heater was on and working fine during the drive there.

The car was off while we were eating.

The back window got a bit fogged up while we were sitting there, so as we were leaving I turned on the rear defrost - no clicking or blinking dash lights. While it was on I also turned down the temp on the driver's side - no problem. I don't remember if Darryl adjusted his side as well.

We drove for about 20 mins, (heater on), stopped at a store.

Drove for about 15 - 20 mins more, (heater on), and stopped at costco.

Left costco - heater was on. Darryl adjusted the heat on the psngr side and the heater went crazy:
* The display went black leaving only a small L shape in the middle
* The fan alternated between high/low continuously.
* The heat and front defrost kept cycling on/off - like it was cycling through each of the "modes" over and over.
* Pressing fan/mode/off buttons did nothing.
* The battery voltage dropped below 13 and was continuing downward.

We stopped in a parking lot and pulled the 2 HVAC fuses. It started right up and drove home just fine.

I pulled codes when I got home and the only 2 are:
C1255 H
B0432 H/C (rear defogger relay circuit)

I have service manuals for it and have looked over the wiring diagrams. I've also read the possible causes and diagnostic procedures B0432 error code. Rather daunting.

The cigar lighter, RTD switch, Traction control button, Fuel Door release, and Console Power Port wires are part of the same wiring bundle and they all work fine (hmm.. maybe I shouldn't say that too loud).

Does anyone have any suggestions on what to check for first?
If there is a problem in the defogger system/circuit - why would the heater wait until after the defogger is off to malfunction?

What are the chances that I'll have to replace the new controller now?

Thanks,
Lanna

wldstrk98

anyone??

dpd

are you sure when puppy spilled over your coffee it didn't get into the floor panel[bcm/rear defogger relay are in there]? also make sure the grounds on the r/f a-pillar are clean and tight.

wldstrk98

Hi,

Thank you for responding - I was getting a little frustrated by the lack of responses.

The coffee was contained to the area below the heater control pannel. It looks like the coffee flow was stopped by the bottom bar of the frame the control unit and radio bolt into. I checked behind it and there was no coffee. I also checked under the carpet on both sides of the control unit and they were dry.

We have volt/ohm meeters but no scan tool so I don't know where to start.

I'd appreciate any other ideas/suggestions anyone has!

Thank you very much,

lanna

dpd

first,pll up the right front floor borad and see if you have anything in the fuse box/bcm area.then make sure the grounds that are bolted under the r/f a-pillar are clean and tight.