OK, here’* the deal. I’ve got a 2000 Bonneville SE with the dual A/C controls. Problem is that the AC will only blow cold out of the passenger side vents and only “room temp” air on the drivers side. Searching the forums here shows others have reported the same problem; responses were that either the flap, or door, in the air mixing chamber could be stuck or the solenoid controlling the flap could be bad. Sounds reasonable, I’ve seen this problem occur before in other vehicles due to a vacuum leak.

So I bring it in to my dealership to check it out. I’m told that I am low on coolant and that the “default” in this situation is to blow cold only on one side. Huh? I’m also told that I have a leak on the AC hose that connects to the rear of the compressor, BUT because of this connection, I will probably have to change the compressor ALSO since there is no way of knowing which is the bad one or possibly the fitting is corroded due to the leak.

I’ve checked the coolant level myself, not that hard to do, and it shows in the blue on the gauge. Now I’m really skeptical about the whole deal. I don’t even think that they even considered the air chamber flap at all and why are they telling me I’m low on coolant when I don’t see that. Could their equipment be that much better than my home unit.

I’ve always gotten really good service from these guys in the past, but now I’m just a bit troubled by the whole thing and I’ll be bringing it to another mechanic that I trust to confirm the leak, or not.

Sorry about the long post, hope someone will read to the end, any comments?

cajun

I know this may not be much help, but according to the '97 FSM H-body manuals, for Buick and Oldsmobile dual climate controls diagnosis, there is NO mention of low refridgerant as something to check or something that would cause this. All troubleshooting/diagnosis information points to faulty airmix door or HVAC programmer or poor electrical connections.

Also, searched the site and I see a few others have posted but very little responses.

We really need someone with a 2000 FSM to help out here. Or if you get it re-diagnosed and fixed by another machanic, let us know what the problem was for future reference.

I've just realized that I did not do a follow up to this post.

Took the car to a trusted mechanic shop. He was a bit skeptical also that low coolant would be the culpret, but what do ya know, sure enough, had a realy small leak at the back of the compressor.

He changed the compressor, recharged the system, and now all is good. Best thing was that he did it all for less than half the price of the dealer estimates.

cajun

Thanks for posting back. So, low refridgerent sets a default mode to blow to one side. Hmmmm...never knew that one. We will add it to the wealth of BC knowledge.

Glad to hear everything is back to normal.

Where is this coolant gauge that reads blue.My AC doesnt blow cold.

Coolant gauge? jdq, it sounds like you need A/C service. You're probably running low on hfc-134. Does the A/C compressor engage?

Cajun wrote
" I’ve checked the coolant level myself, not that hard to do, and it shows in the blue on the gauge"
What is this he is talking about, not to hijack..

Hiya guys

Mark... problem is already fixed.

The gauge I think he'* talking about is an over the counter refill can you are now able to buy at autoparts stores. The coloring is "supposed" be indicate the proper levels for "most" cars.

A little personal experince on my 97 talking here. I had my AC compressor swapped and refilled by a friend. Without looking at the manual it was refilled to the standard psi which would be blue/green on that gauge.

In reading through the factory service manual (best tool you can invest in) it stated that the specification for filling was much higher than the "normal" range. While the gauge read blue/green.. I'd put some money down that the system was actually lower than it should have been.