Hi there. Well, my 97 is starting to show it's age. Have a few things going on and I'd like to know if anyone else has ever experienced these:

1. The air conditioner turns itself on and off - randomly. The buttons don't work when it's "off," but all the lights come on when it turns itself on. The boys at ECS tryed replacing the whole panel with a new one, but the same thing is happening, so it's not the panel.

2. The windshield wipers ramdomly turn themselves on and off when in the "off" position. And now they're mostly just "on." We pulled the fuse so I can drive until this gets fixed. Does this sound like the wiper motor or something else?

There doesn't seem to be a coorelation between the air and the wipers, but maybe there is. I noticed the wipers turning off when I hit the breaks. The air problem started first.

On a positive note, I have a new vararam, Ligenfelter fuel pump (that went too) and a good street tune, so the car is feeling great. New headers, seats and wheels/tires are next on the list.

Would love to hear if anyone has had these problems and how they fixed them.

 

BCM?

 

Sort of wondering the same thing with the BCM too.. any evidence of water on or around it? Checked the udders?

 

Ok guys, with the exception of the BCM being on the class 2 serial bus along with the HVAC control, how does the BCM involve either of the OP's problems?

 

Poor grounds are often the source of screwy problems . I would check them all ( there are a lot of them ) before I blame the BCM . Good luck

 

No doubt the C5 is extremely sensitive to grounding issues, but how would the loss of a ground(or high resistance ground) cause the wipers to come on all by themselves?

 

I'm thinking water in/on the wiper module located at the wiper motor up inside the winshield plenum as the strongest candidate. Can't totally rule out the wiper switch either, but I would be looking inside the plenum first.

 

By AC problem you really mean the whole HVAC control panel goes off? Is this the automatic HVAC controller or the manual controller?

The problem could be the ground pack SP202 which is at the base of the RH A pillar.

I'm thinking the wiper problem is in the motor. Other GM products have a small circuit board in the motor and when it acts up the motor does odd things like not park or keep running.

Under the dash on the left hand side of the steering column is connector C219 which is supposed to be a 6 wire connector with 4 wires in it that are pink, gray, dark green and purple. This is the wiring for the wiper switch. Tr disconnecting this connector. If the motor still runs then it's likely the motor. If the motor stays off then it's likely the wiper switch.

Peter

 

This is all great information - thanks! ECS started checking the grounds (the main ones) and that didn't affect it, but that does't mean it's not some place else. I'll check the C219 connector!

I have not found any water inside the car (we checked that too) but I've only had it since last August, so there may have been another issue previously. We cleaned out the udders - they were full of gunk - but it didn't change anything.

 

If any water has ever backed up and got into the wiper module, screwy things can happen. Just cleaning out udders (although a good thing to do) won't make wipers start working correctly again. Don't rule it out.

 

Today, 03:23 PM #9
GeorgeZNJ
CF Senior Member

St. Jude Donor '08





My Corvette Photos
Member Since: Aug 2004
Location: ECS ROAD COURSE RACING coming to a track near yoo. SIT DOWN, SHUT-UP,HOLD ON ECS 402--503rwhp492rwtq

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I didn't read through all of the links but, if the wipers wouldn't shut off, there's only a couple of things it could be. Switch stuck in the closed position, wiper relay stuck in the closed position. If either were stuck in the closed position getting voltage constant voltage, the motor might be shot. But because it a wiper motor, and could be running for hours on end if you're stuck in the rain, I would think the motor would be a constant duty motor and it might be okay.

 

Instead of questioning other's feedback why dont you just give ideas for her to try?

 

Simple. Some folks like to throw out suggestions without foundation, and subsequently, the poor person that is troubleshooting is off on a wild goose chase.

It just gets goofy sometimes....like a bunch of chickens cackling....."maybe it's this...maybe it's that"...

Why not make suggestions of substance based off the service manual schematics or personal experience directly related to the OP's problem(s)?

Finally, if no one ever questions all the "maybe it's this" type suggestions, they get regurgitated in future posts as possible troubleshooting ideas, techniques, etc.

 

Most all interior commands go through the BCM. If water gets onto it from plugged up udders, then some of or many of the body controls could easily get messed up. The BCM receives inputs from the various devices, switches, sensors and so on, associated with it ...then issues commands to various relays to actuate this or that, based upon its firmware programming.

Have you pulled your codes yet?

 

Nope - we ran out of time on Friday. It's going back next week (hopefully CHRIS!) - I just wanted to get an understanding myself of what the problem might be. Here's what I've heard so far:

1. could be the motor is burned out from the water in the udders (they were a mess)

2. Could be the BCM

3. Could be the compressor belt or tensioner

4. the grounds

At least I have something to go on versus searching for a needle in a haystack. I know there are a lot of grounds and that could take hours to go through, so I wanted to see if there was another possible issue to check first. This is all a bit new to me and I hate feeling like I don't know a possible solution - and fortunately, most of the people on CF are very helpful!

 

Check out Bill Curlee's stickies re: electrical issues. Some of that info is pertinent to you.

 

Your description of the AC problem is very vague. Is it the AC compressor clutch, the whole AC control module or what exactly doesn't work. Give me a better description of what works and what doesn't and I might be able to pinpoint the problem further.

For example, if it's the clutch not engaging, relay 34 in the under hood panel could be bad.

I totally agree with this. The BCM suggestion is a total wild goose chase. The BCM does not have anything to do with either of these systems. On the other hand, the PCM controls the AC compressor clutch.

Peter

 

Do you have the manual A/C or Automatic? There are a couple of bulletins that describe problems similar to your description. Both of them offer the same solution to the problem.

HVAC Controls Intermittently Inoperative or Improperly Responding (Reset HVAC Controller) #03-01-39-004 - (Apr 14, 2003)

HVAC Controls Intermittently Inoperative or Improperly Responding (Reset HVAC Controller)
1997-2003 Chevrolet Corvette
Condition

Some customers may comment that the HVAC controller may have become intermittently inoperative or erratic in operation. In most all cases, the HVAC controller will function normally when the vehicle is examined by the technician. Additional comments may include a variance in the air temperature from driver to passenger side air vents.
Cause

The customer may be turning the temperature **** from warm to cool or from cool to warm very rapidly. Under certain conditions, if the temperature **** is rotated very quickly, it may exceed the ability of the HVAC controller to interpret the desired action.
Correction

Cycling the key to the off position will power off the HVAC controller and reset it, restoring normal function to the HVAC system on the next vehicle start. Instruct the customer that this is a normal function of the unit and that no repairs are necessary.

Service VME - Heater Air Conditioning ( HVAC ) Control Head Does Not Respond - DTC electrical #PI01003 - (Apr 9, 2003)

Service VME - Heater Air Conditioning (HVAC) Control Head Does Not Respond - DTC electrical
.
When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.
SERVICE VME

Corvette (Y-Body) 1997-2003 Heater/Air Conditioning (HVAC) Control Head Does Not Respond
A condition exists where the HVAC control head may not respond if the temperature control **** is rotated to quickly back and forth from hot to cold. The HVAC control head may not respond to requested temperature changes or it may have warm air blowing out of one side of the dash and cold air out of the other side. If this condition exists it should not be considered a faulty HVAC control head.
Replacing the HVAC control head will not eliminate the occurrence of this condition.
The owner should be advised to rotate the temperature control **** more slowly to prevent this condition from occurring. The owner should also be advised that turning the key to the off position will clear this condition and allow the HVAC control head to resume normal operation.

Bill

 

You don't say how many miles are on your car which would give us more information on how used certain control switches are.

I'm sure the two problems are not related.

The wipers are either a bad motor or a bad switch. Try getting some electrical cleaner and spray the switch area and see if that helps any ?

Have they checked the high and low pressure on your AC to see if you have enough freon ?

Do you have the digital or manual controlled AC system ?

 

Good morning everyone. My car is an automatic with 86k miles on it. It's had three previous owners and I bought it in Carlisle last August when someone traded up at the show. When I got it, I had every fluid in the car changed and the steering column locked, so that got fixed as well.

Here's the details on the air - I can't turn it one...the buttons don't work. When I try to turn it on, it won't come on. Then randomly, it turns itself on and works fine - and I can control the temp, level, etc. We removed the entire panel and replaced it with a different one and the same problems occur, so it's not the panel. Freon is not the issue either. I don't know how else to explain it except that it just works when it wants to.

Let me know if that helps.

PS - I have not had a single "error" message come up at all - the car is running fine otherwise.