2002 Buick Lesabre Ltd A/C Question

[2buicks]

I hope someone can offer some suggestions on what seem to be an intermittent problem. My 2002 Ltd has always blown cold air without issue, but my wife came home the other day and tells me the air conditioning is not working. The car sat in the driveway all day and I went out in the early evening hours and all was working fine. Last week, I took the car to a local Auto A/C shop I use, and he said everything is fine, freon is to the level it needs to be, no problem found. A few days ago, I went to move the car out of the driveway, very quiet inside, then I realized the A/C is not blowing. Popped the hood, it was dark outside so I couldn't see if the compressor was turning, returned to the inside and the A/C was blowing fine. I just now went to the Auto Parts store, came out and the same thing happened?? A minute or two and a blast of cold air that would freeze you out! Almost seems like a sensor problem or maybe electrical? If anyone out there has some insight, I would greatly appreciate it. My wife is trying to convince me she needs a new car, but the Ltd only has 64,000 miles on it! As in the past, thanks guys for any help

[Tech II]

Little confusing......are you saying it's not blowing air at all, or are you saying it's blowing air, but it's not cold?

[brcidd]

blower motor inop is a very common problem-- bump it and it runs- means you need a new blower motor.

[2buicks]

The car blows cold air, I wish my 97 worked as well. It's just when you shut it off and restart it or the first start of the day, you have to wait awhile until the A/C and fan motor kicks in. This is something new, it has always blown air as soon as the engine starts; it might take a few seconds for the ice cold air to move with it, but the fan motor has always come on right away! Now, you have to wait a good 30 seconds to maybe a minute for both to come on! Could there be a fan relay which is delaying the fan?
I haven't looked at the compressor to see if it is turning while this is acting up! Sorry if I have confused anyone, but the A/C is working with the fan motor just fine. It's the delay of both that has me puzzled.

[Tech II]

Is this autotemp or a manual system?

[2buicks]

Auto temp

[imidazol97]

Originally Posted by 2buicks

then I realized the A/C is not blowing. Popped the hood, it was dark outside so I couldn't see if the compressor was turning, returned to the inside and the A/C was blowing fine. I just now went to the Auto Parts store, came out and the same thing happened?? A minute or two and a blast of cold air that would freeze you out!

The blower motor is a round hump on the bottom of the HVAC box where the passenger's left foot would ride. Tap with your toe of your shoe (or you hand) on the bottom there when the car is ON and the heater is not blowing. It will probably start up.

At the parts store, you probably started it with the vibration from the hood slamming when you put it down.

The brushes stick in the channel and lose contact with the commutator is what I found when I took my old one apart.

To change, it is 3 screws and a rubber air tube for cooling the motor, and it's hard to hold up in place while you get two or the screws started to hold it. The air hush panel cover on the right side under the dash has to come off with a few screws.

[2buicks]

Thanks for the tip, it did not act up today at all, so I will keep an eye on it and replace if problems continues.

Thanks ...........................

[2buicks]

Okay, Imida hit it on the head when he said to bump the hush panel and fan motor will begin to work. We've been doing that and the fan starts, but the fan motor speeds will vary at all temps, seems like the system is continually searching for a fan speed. I see in the GM FAST PARTS CATALOG that there is not only a listing for the fan motor for dual temp control, but also a fan motor control module, both items very expensive. My question, could this whole problem be associated to the control module and not the fan motor itself OR do you think both could be the culprit? Also, is the hush panel easily removed by hand. Somewhere I read that there are built in retainers on these panel covers. Any trick to this removal?

[DeltaP]

Fan motor sounds like is about to quit for good and soon the way you say its hunting for a speed. The motor brushes and commutator are worn to the end of their rope. The control module is solid state so I doubt kicking it'll have any affect as long as its plugged in securely. I'd go with a new fan blower motor. I'd also shop for a better price from Rock Auto, Advance, O'reillys,etc. Yes, the hush panel should have 2 or 3 thumbscrews and come out easily by hand.

[Tech II]

As has been suggested, if the motor doesn't run, tap it......if it runs, I doubt it's the blower control module......one thing to check if replacing the motor.....remove the harness and look at the connection in the harness.....look for black contacts(arcing) and melted plastic(cause by heat generated by poor contacts)......if any evidence of this, the end of the harness has to be replaced(in some cases, just the contacts have to be replaced).....

Remember this is auto temp, so fan speed is not constant......as the interior temp reaches the set speed, the fan speed will slow down.....the only times than the fan runs constantly, is high, and that is when you have the temp set at 60 or 90, in auto temp.....if you go to manual mode, then the fan speed runs at whatever speed you have it set at....

[imidazol97]

Originally Posted by 2buicks

ut also a fan motor control module, both items very expensive. My question, could this whole problem be associated to the control module and not the fan motor itself

Tapping the blower motor may vibrate the wires on the connector next to the BCM and affect contact there.

Follow the wires from the fan motor to the connector that attaches it to the blower control module (BCM). When it's not working, wiggle that connector to see if it is a burned contact in that connector. There are some reports of that being the problem. The pins carry a high load and the heat and a little corrosion increases the heat melting into the plastic holding the pins in place.

I just helped a neighbor yesterday who is a shadetree professional mechanic troubleshoot power windows on a car. No circuit diagram. Finally shadetree pulled the whole cable bundle out of the door into the end of the dash where there's a clamp-together connector. I troubleshot all the cables with my meter looking for a broken wire. Nothing. But putting it back together it worked just fine. I suggested wiggling the cables next to the dash while moving the window. Sure enough, it would make and break circuit. Then looked at the clamp-together connector and the pin for the main power wire showed heat symptoms. The jack showed plastic melt damage. Same thing you might find.

And it could be a BCM problem. Troubleshoot the others first.

[2buicks]

Guys, I can't thank you enough! I'm running gun shy on this one. When I look at Rock Auto, Fast GM parts, Ebay, Advance Auto I see blower motors with cooling tube, I see some without cooling tube, and each type are shown as good for the Lesabre Limited? Motors vary greatly in price. Some feedbacks saying they got a great price, however, the fan noise was unbearable. My wife has convinced me that I should let our local Auto A/C man do this one! I'm not the thin guy I used to be and have doubts if I can work long in the small passenger side floor area, so maybe she is right? My '97, I would have jumped on it as that one I can get to off the firewall. Anyway, I will let all know what he finds tomorrow when I take it in. Thanks again!!

[Tech II]

Just a clarification on this.....a blower control module is not a BCM(body control module)...

[imidazol97]

Originally Posted by 2buicks

Guys, I can't thank you enough! I'm running gun shy on this one. When I look at Rock Auto, Fast GM parts, Ebay, Advance Auto I see blower motors with cooling tube, I see some without cooling tube, and each type are shown as good for the Lesabre Limited? Motors vary greatly in price. Some feedbacks saying they got a great price, however, the fan noise was unbearable. My wife has convinced me that I should let our local Auto A/C man do this one! I'm not the thin guy I used to be and have doubts if I can work long in the small passenger side floor area, so maybe she is right? My '97, I would have jumped on it as that one I can get to off the firewall. Anyway, I will let all know what he finds tomorrow when I take it in. Thanks again!!

I recall there were two different styles of motor for some years. One requires an adapter plate to use the later design. I replaced mine with a Continental from Autozone for $139. I don't have excess noise. I can hear the blower motor when on the 6th manual speed, but then I could hear the original blower motor.

I see that my local Autozone shows both styles for 2002 in stock at the store. When my blower motor finally quit reacting to tapping, I needed one soon. Most stores were happy to order one in at the big box stores. They would have it in 2 days, e.g.. But Autozone stocked them at the stores. Many local stores were out of the 1 they stocked because the motor is shared with lots of Bonnevilles, which were also experiencing failures. But two local stores had one in stock and I picked it up when I went across town to a cruise in that evening.

I found it easy to lie across the driver seat with my right shoulder down against the floor on the passenger side.

Good luck.