ECC display flashes (Update 3/31/08)
 

My ECC display flashes shortly after startup, although the climate control still seems to be completely functional. I've been experiencing this issue for a while since I had a battery problem a while back ( http://www.bonnevilleclub.com/forum/...ic.php?t=86272 ), but I expected the ECC to stop flashing after 40-50 startups. Well, it's still flashing every time I start the car, so I need suggestions :lol:. It flashes for about 1-2 minutes, then stops and seems to function normally. Any help is greatly appreciated!

Bump.

Any ideas here? Why would the ECC be flashing for a minute or two shortly after startup?

Any number of faults can do that. It's pretty hard to take a good guess.

I'd suggest since things work right, that it's possibly some non-critical component. Does your outside temp seem to report the right temp? It's also possible the inside temp sender may be bad. You'd have to check that with an ohm meter.

Outside air temp seems to be accurate. This all began when I had battery problems a few months ago. But all I ended up doing was replacing the battery. Not sure if the two things are related or not.

What about the amount of R134 in the system? My ECC flashes because of no refrigerant...;I gots me a leak at the compressor. That's another one of my winter projects...rebuilding the compressor ;)

Mine had flashed when the car was cold and started up or when it hit the cold air a minute after coming out of the nice garage. I added R134A this summer and it hasn't flashed since. I suspect when the AC system is cold the R134 pressure dropped below the needed pressure for the minimum switch and triggered the flashing. That's even though the system was requesting AC, is was still tell me there wasn't enough freon at 20 deg. F.

I guess I can take a look, although I had a new condenser installed in the last year because the old one leaked. Plus the A/C worked fine all summer. I don't know why it would act up all the sudden. But it's worth a shot.

Any way to scan the ECC to see what the problem is? Or is that a dealer thing?

I realized something tonight since the weather's finally starting to turn a little colder. There's no heat coming out of any of the cabin vents. The air it blows isn't freezing cold, but it's much cooler than it should be blowing in 50 degree weather.

Would this be an airmix door malfunction?

Starting to look like it. Remember my redneck fix topic? It shows a view in through a hole in the dash support bar. Remove the glovebox door and liner. Get a flashlight and look in there.

Now adjust your heat full cold and full hot. Do you see the actuator move? Does it ever try to 'home' itself on startup?

Time for a revisit to this topic....


The car DOES have heat... just not all the time. Sometimes the air blowing out of the floor/panel/defrost is nice and warm; other times it starts blowing before the engine warms up and remains cool for the duration of the drive (usually I just turn off the ECC when this happens). I haven't noticed any pattern to when the air blows cool or when it sends warm air through the vents.

Any ideas? Probably not an airmix door? Any chance its the sensor that reads the cabin air temperature reporting a faulty reading?

You can check the cabin air temp sensor with this:

http://www.bonnevilleclub.com/forum/...e=article&k=24


Have you verified your airmix door is moving full-travel? All the time? Use my procedure above. It works better at night without any ambient light to constrict your pupils.

Ben, my money is on an airmix actuator. They can be intermittent before they meet with catastrophic failure. Pulling battery power seems to exacerbate the problem. As Will suggested, pull the glovebox out and witness the motion of the door arm while you run the temp from max to min a few times. It should be smooth with no hesitation or jerky motion, and it should go to the maximum extent of travel in both the cool an hot directions. Another test is try to move the arm by hand (e.g. using a long, slim screwdriver). If you can move the arm by hand, your gear is split and is slipping on the shaft. There is no cure for this other than replacing the actuator motor. You can use the redneck fix until you have time and resources to replace the motor.

Sorry for not being around to help on this one Ben, but the other bozozs have pegged it. 99.99% sure it is the actuator. Stop on over so we can look at it and if it is the actuator, we can do the "redneck" fix for now and work on replacing the actuator later.

Also, until we look at it, it might help if you take it out of "AUTO" mode and just run it manually using the "temp", "mode", and "fan" speed adjustments. Set the temp to 85* max (not 90* so you don't drive the actuator arm all the way to full heat and cause slip) and it might work the majority of time. I remember when mine failed, that setting it to 90* would cause the door to be forced wide open and then it would cycle to colder air. Shutting the car off and restarting also worked quite a few times to "reset" the air door, but we need to get you fixed up as soon as possible.

Thanks for the responses, everyone. I appreciate the information. I've been working a ton lately and just got around to checking this thread after a couple days. I'll try to do the airmix test this week sometime, but if I don't get it figured out by Saturday I'll have to do it after I return from Christmas back in Iowa. I'll report back when I get a look at the airmix door.

Bob - I don't know if I'll be able to come over this week. I've been working 12-14hr days, so it limits my relaxation time at home. However, I might take you up on the offer after the new year ;). Perhaps we can trade labor in the same day?

I have this exact same problem. I live in Minnesota, so when you can see your breath in the car after driving 1/2 hr, I need it fixed soon. The same thing, after a battery problem, the temp light blinks, then stops after a couple of minutes. One thing, if I let the car warm up, then shut the car off, and immediatly start back up, the hot air blows, until the computer reads something and then the blinking starts, eventually stops and from the time the blinking started, blows cold air. My compressor leaked out all the freon this summer, but up until the battery problem, my heater worked awesome. something is linked to this battery problem or computer resetting???Help i'm cold!!

First off, welcome to BC amundson.

This definitely sounds like a broken/faulty airmix actuator. Here is a post that should guide you through the process of evaluating the possible problem and providing info on how to fix it. Also includes a "temporary" solution to give you heat until you fix it.

http://www.bonnevilleclub.com/forum/...71&highlight=A

Haven't done much posting in a while, but I have an update on this issue.


I got my transmission rebuilt about a month and a half ago, and up until then the car was still having the issue of intermittent A/C or heat with a flashing ECC display. However when I got the car back from the tranny shop the problem had magically disappeared. The ECC didn't flash and I had complete control over the temperature of air coming from the vents.

Here's where it gets funky: A couple days ago I was doing some tuning work with Thomas Stoppenbach (PDXGTP), and we decided to swith to a stock PCM I had laying around. I disconnected the negative battery cable, swapped the KS module and the PCMs, hooked up the battery, did a quick flash to the PCM, and restarted the car. Lo and behold, the problem returned. All I touched were the battery and PCM, and I'm thinking the PCM has nothing to do with it.

What kinds of tests should I do? I'm not much with electrical, but I'm thinking the problem has to some sort of bad ground related to the negative battery cable. What would be the best ways to tell if the cable is loose and/or bad?

Also, not sure if it's related, but the car has been idling a little oddly from time to time. It'll idle down really low and lope like a big V8... sounds like it's about to die. It also threw a "Lean Bank 1" CEL the other day. We were thinking fuel pressure regulator, but I figured I'd add it here in case there could be a common cause.

TTT

Anyone?

That is the most bizarre thing I have ever heard of, as far as the ECC. Not really sure anyone has ever had it work again, normally, and then fail again. Certainly no precedence here, that I am aware of, that a loose negative connection caused the ECC to go wacky, but I suppose it could.

As far as the negative battery cable, wiggle everything at all connections and try to rotate clockwise/counter clockwise. If they move they are not tight. One other thing to check is to see if the terminal face on the negatave post of the battery itself has been "chewed out" by the ears on the cable.

It's weird, isn't it? For over a month it worked fine.... no flashing, no odd behavior. I guess all I can do is wiggle some stuff, eh? I was hoping someone could point me toward a "master ground" or some other source that sounded suspect. But I guess as far as automotive electrical is concerned there's nothing more "master" than a battery cable.

I'll give it some attention in a couple weekends and see what I can find.

The HVAC system most likely gets its ground from the ground bus on the passenger side (I would need to look it up to make sure) and if that ground was an issue, tehn I would expect a few other things to be acting up as that is a shared ground for many components. Is there anything else on the car, electrically, doing strange things?