94 Buick Park Avenue Ultra Radio and climate control malfunctioning?

Prennijs

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94 Park Avenue Ultra
Just bought a 94 Park Avenue Ultra that has an issue with the radio and climate control. The radio will turn stations on its own as well as turn the volume up and down. The A/C and Heat will activate intermittently without me pressing a button. The temps go from cool to warm. I have to repeatedly turn it off. The steering wheel controls don't seem to work for either. Anyone know what the problem is? Fuse or relay maybe?
 

HotZ28

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1996 Roadmaster Limited Collectors Edition 58k - 1996 PAU
The radio, climate control & steering wheel controls are all combined in the same circuits. Has the car ever had any aftermarket parts installed in that circuit? If not, that problem is impossible to troubleshoot from here and you may need to visit a special audio, climate control expert with that particular car!
 

Prennijs

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94 Park Avenue Ultra
The radio, climate control & steering wheel controls are all combined in the same circuits. Has the car ever had any aftermarket parts installed in that circuit? If not, that problem is impossible to troubleshoot from here and you may need to visit a special audio, climate control expert with that particular car!
The previous owner did have a new alternator installed last week. Not sure if that would cause it. Would installing an aftermarket radio produce the same results. I mean, I wouldn't think so, but this is my first Buick so I'm not that knowledgeable about them
 

BuickGirlFromMars

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1999 Buick Park Avenue Ultra (Supercharged)
Anything that intereacts with a body control module. Now, Im not for sure, but I believe on the previous gen park avenues(electras), the car would only have a BCM if it had higher trim options and gadgets(which i think park avenue was that trim), but the generation changes in the 90s for a lot of the gm luxurys the cars got BCMs standard. If so, you have all those components interacting with the same module. including a radio. But Im not certain.
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2007LucerneCXL

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2007 Lucerne CXL. and 1995 Lesabre currently, past 1973 Riviera, 1968 Riviera
Not sure what you are saying, was or is a aftermarket radio installed? If yes the answer is to start by checking out the wiring harness and connections for issues like bent terminal, not connected, broken wire, etc. Also check fuses and relays, there's under hood, dash and passenger front foot well I believe. Not knowing anything about the vehicle history on what may have been done as in other posts it's best guessing on what to look for.
 

Prennijs

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94 Park Avenue Ultra
Not sure what you are saying, was or is a aftermarket radio installed? If yes the answer is to start by checking out the wiring harness and connections for issues like bent terminal, not connected, broken wire, etc. Also check fuses and relays, there's under hood, dash and passenger front foot well I believe. Not knowing anything about the vehicle history on what may have been done as in other posts it's best guessing on what to look for.
No, the previous owner didn't install any aftermarket radio. Bought it off an older couple at 81,000 mi. But I will definitely check the fuses. I'll update on what I find
 

Prennijs

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94 Park Avenue Ultra
Does the car have automatic climate control where you can set a specific temperature? If so, the car uses a blower control module. When they go bad, a common symptom is the blower motor coming off and on intermittently. The radio may be a separate problem.

https://www.rockauto.com/en/catalog...g,blower+motor+control+module+/+resistor,6557
Yes, it has the automatic climate control. I'll try to grab one of those tomorrow. Do you think a simple one radio swap would solve the issue?
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LARRY70GS

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98 Riviera, 70 GS455 Stg1
Who knows, maybe, maybe not. The steering wheel controls can commonly not work when the radio is replaced with an aftermarket one. That's why you were asked that question. I would check all the wiring to the radio. When you buy a used car, there is no telling what previous owners have done to the car.
 

Prennijs

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94 Park Avenue Ultra
Who knows, maybe, maybe not. The steering wheel controls can commonly not work when the radio is replaced with an aftermarket one. That's why you were asked that question. I would check all the wiring to the radio. When you buy a used car, there is no telling what previous owners have done to the car.
Here is a video of what is going on. Hopefully it gives more details.
 

LARRY70GS

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98 Riviera, 70 GS455 Stg1
That is very strange. Electrical problems are the hardest to diagnose without the service manual. I know the 97 and up climate control modules were famous for problems, and there are plenty of rebuild services for them on Ebay, but all I see for the 94 is used replacements.

94 buick park ave climate control | eBay

Normally I say diagnose before spending money on changing parts, this might be a good investement,

1994 Buick Le Sabre, Park Avenue Shop Service Repair Manual CD | eBay

Your problem might be as simple as a bad ground. Could also be a problem with the steering wheel controls. One thing you could try is removing the air bag and disconnecting the feed for those controls. If that fixes the problem, you will have isolated it to those controls. Won't cost you anything either. Make sure you pull the air bag fuse before though, just to be safe.
 

Drakito

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2003 Park Avenue Ultra
The clockspring in the steering wheels can wear out. Debris can also get into the clockspring and short terminals across to each other. The system in these early steering wheel control cars uses a single wire for the radio and climate controls. They use different resistances to ground to send the signal down the wire. The clockspring has the airbag wiring, power and ground, the horn wiring, a ground and the signal, and the ground wire and signal wires for the steering wheel controls, usually in that order radiating out from the center. When you press each control it grounds through the resistor built into the switch. The climate control and the radio read the resistance and act accordingly.
Here is a video on how it works:
I have to admit, your 94 has a different design from the one in the video. It has a flat plate with spring loaded fingers that trace a copper raceway that is hard mounted to the column. The fingers are on the wheel side.
That being said, does your horn work correctly? Or is it intermittent depending on steering wheel position? Any airbag lights?
Another known issue can be the radios of these era. They like to have internal shorts left and right.
I would go in this order to diagnose.
1. Check to make sure the horn works through all angles and rotations of the wheel. If if does go to 2. If it does not, first take compressed air and blow the gap between the steering wheel and the column clean. Recheck. If it still has issues, get a new clockspring installed.
2. Remove the radio, but leave it plugged in. Unplug just the antenna and see if the controls start working normally for the climate control. If they do, reground the antenna. If they don't, unplug the radio completely. If they start working now, new radio and you are done.
3. If they still go crazy after #2, reinstall the radio and remove the climate control. Check for proper operation of the controls. If it works fine now, install a new auto climate control box and you are done. If it is still crazy after all 3 tests continue.
4. Check the main grounds for the steering column, dash, and battery. The dashboard is usually grounded in each kick panel. The column is usually grounded to the dash support, or sometimes to one of the 4 mounting bolts you see when you remove the lower panel below the steering wheel.
If the grounds are loose, corroded, broken, etc, take a wire wheel and take all the paint and corrosion off the area the ring terminal mounts to. Clean the ring terminals and body area with the wire wheel to bare metal. Reinstall with a cleaned bolt, or a new larger bolt to make sure it stays tight. Paint over the top to inhibit further corrosion. Recheck, if you fixed it, yay! If you didn't, it could be the actual switches in the steering wheel itself.
These early cars do not have a computer interpreting the signals to resend them to the climate control or stereo, it is all an analog signal.
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Prennijs

New member
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94 Park Avenue Ultra
Just an update. Checked the ground to the alternator and it was loose. After tightening, the radio seemed to stop acting weird for now. The climate control as well. I also have another problem I just noticed. When the AC is on, it blows cold on the driver's side but heat out the passenger, irregardless of the passenger climate control. How can I fix it? I think my uncle said something about a blend door or something
 

2007LucerneCXL

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2007 Lucerne CXL. and 1995 Lesabre currently, past 1973 Riviera, 1968 Riviera
Blend door actuator is one possible cause the other may be the vacuum lines control. They may have come off, cracked etc easily checked before digging into the dash. There are 2 diagrams below as I'm not sure which one would be in your model and the lines are under the dashboard and in the engine bay.
1992-1995 CA / C CONTROL SYSTEM / VACUUM (CJ2) Buick Park Avenue
9706204M09-015.png

1992-1995 CA / C CONTROL SYSTEM / VACUUM (C67) Buick Park Avenue
9704174M09-017.png
 
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