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AC/Heat question-98 STS

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I got my STS a bout 6 weeks ago,but since ive got it when I turn on the AC it blows heat out of the driver side vents and AC out of the passenger side vents.........plus even when the heat/ac is off and I get on the highway one of the driver side vents gets very hot to the touch??The car does not run hot so im kinda puzzled??

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This could be either a low refrigerant condition or an actuator issue. Pull the diagnostic codes and post them back.

'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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Get a pencil and paper ready, then turn the key on and, on the A/C console, press <OFF> and <PASS Warmer> simultaneously for a few seconds until all the dash lights come on, then release the bottons. The OBD codes will be presented for each of the car's module in sequence on the Driver Information Center. Write them down and post them here.

The codes will be of the form


where XXX is a three-letter acronym that indicates the car's module, the letter P in the example will be one of P(owertrain), B(ody), C(hassis) or U for network, and the nnnn in the example is a four-digit code. The HISTORY in the example may be HISTORY or CURRENT, and on some cars it will be abbreviated as H or C. CURRENT codes are of the most interest.

The most important thing is the four-digit code, with the letter preceding it a close second, and the HISTORY or CURRENT is very important. The module that threw the code will be apparent from the code in most cases.

If you miss a code, wait until you see the prompt "PCM?" and touch <OFF> to start the codes over. When you are done, push the AUTO TEMP knob all the way in, or press the INFO RESET button above the radio, or turn the key off.

-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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