QuestionQUESTION: Hi All
I am having a problem with a 91 Buick Park Ave. When I try to use the A/C it won't come on. The blower comes on and the temp setting on the control comes on but the compressor won't come on. This car has climate control. The Econ button stays lit and it won't let me change any of the settings by pushing any of the other buttons. Any help will be appreciated. Thanks
ANSWER: Hi Al,
I'm going to copy an answer from another poster that I just typed out -- it's the same concern, but I have altered it for your vehicle.
Most times, this is a low refrigerant condition in your A/C system. In order to prevent damage to components, the logic shuts down operation if the refrigerant pressure is below a certain value. Have a certified shop diagnose the A/C system.
The reason I say diagnose: these systems are pretty complex, particularly if it's automatic A/C, and there's varying reasons why it can stop blowing cold air. It can be an electrical issue (poor connections, faulty electronics), a mechanical condition (linkage disconnected, etc) -- to name a few. Also, the possibility of a Technical Service Bulletin (TSB) that addresses this issue as well -- this car has 53 TSB's, and several of them relate to this concern.
Most times, however, it is a refrigerant leak, and the normal fee for a charge and leak test is approximately $75-200 (due to the cost of R-12.. unless your car has been retrofitted). Normally, this includes an R-12 charge, an electronic leak test, and if necessary, a dye. Sometimes, the dye is not checked for until the system leaks enough to stop -- if it's a small leak (sometimes it takes a couple of weeks). However, it can be verified with a black light, and repaired properly.
Good luck!
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QUESTION: Thanks for the reply. I have checked for low refrigerant and it has enough. It has been retrofitted to R134. I also checked the low refrigerant switch and it is working,( shows good with a continuity meter) I just don't know why the control won't change from economy mode and the compressor won't come on.
AnswerAl,
Normally, forced Econ mode means the A/C programmer is not getting the proper feedback on the input circuits. The explanation is too in-depth for here, but one of the 53 A/C TSB's has to do with forced-Econ mode. The TSB# is 91-1-17 -- I would love to give it to you, but alas, it's not mine to give out or post here. You might be able to find the TSB online, or visit www.alldatadiy.com for service info subscription. If you're good with a multimeter, and can interpret the diagnostic charts, then you might be able to track this down yourself -- it could be simpler than what is apparent.
I might suggest a trip to the dealer on this one. The diagnostics on these cars had a number of service manual revisions, and numerous problems. Good luck to you.
