1985 Riviera Factroy Service Manual--ECC Problems

[Guest bigskymusiclover]

Greetings, I am having some problems with my Electronic Climate Control System in my 85 Buick Riviera. Would anyone have that section of the service manual they could email me and or help get this bloody system fixed ;-) My system is all Electronic no vacuum stuff at all. THANKS

[DAVES89]

OK now you have to tell us what the problem is. Does the CRT light up? Does the fan run? Does the fan shut off when you turn the car off?

[KDirk]

If this is an 85 Rivi as posted, then it has no CRT. May be digital, but different from anything in the 86-93 Rivi or 88-91 Reatta. 86 was the first year for the CRT setup in the Riviera.

Need some clarification.

KDirk

[Guest bigskymusiclover]

No it don't have a CRT display, just smooth touch buttons! The floor vent I talk about is the defrost vent I believe!

Post 1:

Greetings, been fighting a demon on my 85 Riviera for a while now and with winter fast approaching here in MT, I gotta get the heater fixed. I guess I should start from the beginning. One day the ECC system decides to go "Haywire" the door that's right inside the floor vent center of the dash just kept running over and over again. So I watched it and it would try to close the door run out of steam and open again and try to close again. So I stuck a stick up in there to hold the door shut. In retrospect a bad ideal, all was well for about 20mins. Next the entire system went dead, and went to full blower ice cold air. (at the time it was still winter here). So the only way to fix that was pulling the fuse. So I replaced the ECC head unit. The replacement started smoking as soon as I turned the key. Now all the ECC system dose is sit there and flash at me, and not very often I will hear that door cycle and some other motor moving something. I have felt heat once, but 99.9% of the time it just spits out a low flow of cold air out the floor vents pushing buttons on the ECC has no effect. So yesterday I went out to the junkyard and pulled a new motor that controls that floor vent door. I will replace that and reset the ECC system and report back!

The cars AC system is long not working. The yard dose not have anymore ECC head units, so I am on the search for one. I don't have a service manual for the car.

Am I missing something here, will I have replace the ECC head unit again? Any and all ideals and inputs welcome.

Post#2

I got the motor replaced and the system still is not happy(blinking light) but it is making heat (for how long I don't know). I then proceeded take apart the motor module and remove the bare motor from the housing. Upon testing that motor it appears to have a direct short to ground. 6.6ohms on the 200 scale on one leg and 0.06 on the other leg to the motor case.

Edited August 28, 2013 by bigskymusiclover (see edit history)

[Barney Eaton]

I see you have posted the question on the Riviera forum, they should be able to help

[DAVES89]

Sorry bigsky I thought the '85 had a touch screen and that we could help. There is an '85 in a yard about 20 miles from me. I would think that the controller is bad, however the call is yours.

[Guest bigskymusiclover]

NP I posted on the Riviera section and they said to post over here as-well. I am starting to think the ECC head unit is bad again. Find out if you could and don't mind how much they would want for the ECC. It sits under the radio and just has smooth touch buttons. Thanks

Sorry bigsky I thought the '85 had a touch screen and that we could help. There is an '85 in a yard about 20 miles from me. I would think that the controller is bad, however the call is yours.

[DAVES89]

There are about 20 at Car-Part.com--Used Auto Parts Market Just look for ac controller

[Guest Dan Gibbs]

Oh no!!! Alphabet-soup-acronyms colliding!!! Is it an ECC or an ECC?

ECC - Electronic Control Center

ECC - Electronic Climate Control

ACRONYMS - Assume Correct Recall Of Nomenclature - Your Mind's Slipping

The "Your" in this case is my mind - electronics is chock full of these damned acronyms that confuse the hell outta me when trying to learn something new where the alphabet soup has been re-purposed for another technology....SHEESH!

Cheers,

Dan Gibbs

[Guest Mc_Reatta]

Any chance of getting some photos?

Just to understand, your system uses motors to open and close all the vents not vacuum servos like a Reatta (does other than our blend door)?

How many vent options do you have?

[Ronnie]

This may help but not everyone uses the same interpretation.

Acronyms & Abbr.

Frequently Used Acronyms and Abbreviations

More Automotive Acronyms and Abbreviations

[Guest bigskymusiclover]

Here are some photos! Yes it's all motors, not any vacuum that I know of. "ECC - Electronic Climate Control"

Any chance of getting some photos?

Just to understand, your system uses motors to open and close all the vents not vacuum servos like a Reatta (does other than our blend door)?

How many vent options do you have?

Edited August 29, 2013 by bigskymusiclover (see edit history)

[Guest Mc_Reatta]

Sure looks like standard. Have you pulled out the glove box to see if you have a HVAC control unit behind that does the work?

The module in the dash is probably just a head unit that tells the control unit what vents to open and how to set the blend door. So just changing the unit in the dash might not solve the problem if its in the control unit.

Wish I could find a photo, but can't locate one.

[Guest bigskymusiclover]

Really? The head unit in the dash is about the size of the main computer and has three big wire-looms that connect in the back? I did not think there is more to the system then that!

[padgett]

Unless the head unit has about seven vaccuum hoses, it is probably not the controller. GM has used vaccuum HVAC servos since the '50s.

[Barney Eaton]

Glad you received such outstanding support from the Riviera group. I strongly agree with Padgett, you unit is a combination of electronic unit in the dash and another unit behind the glove box. I have a 1985 Cadillac, Brougham, Eldorado & Seville service manual and believe your unit is closely related. The Cadillac dash unit is layed out slightly different than yours. Also, on running copies, there are 64 pages in the Cadillac manual not an easy copy job. Pull the glove box and look for the link coming out of the top of an aluminum box. That link is attached to the blend door. By changing the dash unit temp between cold and hot, that rod should move to its extremes. The next thing is to check the vacumn line going into that box. Somehow check to see that you have engine vacumn. It is quite common on Reattas for the plastic check valve to be broken/cracked/damaged and little or no vacumn is getting to the ECC controller. Sorry but at this time I cannot even attach single photos or pages because my old scanner will not work with my new windows 8 machine, ain't modern technology great? Also, for some reason I cannot hit ENTER and get a new paragraph. Do I have a bad setting somewhere?

[Ronnie]

The tutorial in the link below has photos that might help. It shows the rod Barney is referring to.

No Heat - Troubleshooting - Reatta Owners Journal

[DAVES89]

I just got back from Gibson's the local U-Pick I go to and they are done to one 81 Riv. The rest are gone. However I have it on good authority that the 84 ECC is the same. Having said that Barney/Padgett are correct that there are aprox. 6 hoses that lead to the controller. I would make sure all your "hard" pieces are intact and that your vacuum hose are good. I think I can come up with what you need as the '85 is at the other yard. Just check out your system and report back with your findings.

[Guest bigskymusiclover]

Thanks guys, here is a shot of 81 so they say, I had one that style in there before and it worked just fine. 1981 Buick Riviera w/ touch screen climate control | Flickr - Photo Sharing!. I am off to the yard today to dig in to the junkyard car, I don't trust myself on my car unless I had some practice on the junkyard car. The junk yard car is a 83 but its missing the ECC. But should have all the other parts!

[DAVES89]

The '83 is NOT the same but is highly coveted on the RIV site. Not the push button part, but the part behind the glove box. The rod unsnaps from the clip, remove 3 screws and unplug the unit. You can ask almost what you want for it...

[Guest Mc_Reatta]

My original suspicion was that you have an electrical problem in the controller that is affecting the head unit. There is the blend door motor, and many coils inside that operate the various vacuum servos that operate all the vents. If any of these have shorted out, they could overload the head unit.

[Guest bigskymusiclover]

The system don't have one vacuum hose to it's name, nothing behind the glove box but vents wires and the twilight sentinel box. There was a 1986-89 Buick that for the hell of it I toke out the glove box and I can see what you are all talking about. My car HVAC is totally electric.

Edited August 31, 2013 by bigskymusiclover (see edit history)