A/C Blowing When I Want Heat

1991 CADILLAC DEVILLE
89,991 MILES • V8 • FWD • AUTOMATIC
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JYOUNGBLOOD
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Basically It's Winter And I Want Heat. Tonight I Replaced The Thermostat, Checked The Air Mix Door, Felt The In Out Lines For The Heater Core And Still No Heat.

But here's the catch. When I Hit Auto And Turn It Up To 90 Degrees The A/C Kicks on and I get 60 degree air coming out.

I've gotten heat for BRIEF seconds when driving and the ECC happened to be set at 90 and I randomly felt hot air on my legs but thats the only tease I get.

Thanks For Your Time,
Jimmy
Jan 7, 2011 at 4:57 AM
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DOCFIXIT
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Need to enter self diagnostics so key on no start Depress on CCP ie.ECC Off and warmer simultaneously 8.8.8 will appear in Fuel Data Center and - 188 in CCP then ..E orF will apear in FDC. See instructions. psot codes will advise
Jan 7, 2011 at 2:08 PM
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JYOUNGBLOOD
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Ok I followed instructions as the diagram shows. Light illuminated on ecc are high fan and off. There are no codes beside the 7.0 on the fdc. What's my next step?
Jan 7, 2011 at 3:18 PM
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DOCFIXIT
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O.K. at 7.0 follow directions in next screen will check for faults
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Jan 7, 2011 at 4:29 PM
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JYOUNGBLOOD
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Sorry but real quick am I looking for differences In the codes in each section or am I looking for something that automatically tells me what's wrong. I'm doing the step but don't know if I need to be upping numbers or something
Jan 7, 2011 at 7:02 PM
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DOCFIXIT
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Looking for codes I will look up and tell you what they mean Get a letter and two digit number
Jan 7, 2011 at 8:28 PM
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JYOUNGBLOOD
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Steps go without flaw until I hit high then low for ecm output I get e96 e1.2 followed by clicking noise
Jan 7, 2011 at 9:06 PM
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DOCFIXIT
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Check operation of Air-Mix door remove glove box looking for rod attached to door see diagram set temp to 90 allow two minutes for programer to move unclip did in move to max travel. next temp to 60 does it travel to min? if good suspect in car pemp sensor behind CADALLAC emblem upper trim panel. remove unplug with OHM meter measure resistence after 30 mins in refrigrator should be high now let warm at room temp does resistence go down?
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Jan 7, 2011 at 9:30 PM
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JYOUNGBLOOD
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ARM moves completely to both sides . Do I need to remove anything besides the glovebox to access it. And what does it look like
Jan 7, 2011 at 9:42 PM
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JYOUNGBLOOD
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The in car temp sensor
Jan 7, 2011 at 9:55 PM
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DOCFIXIT
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behind CADILLAC emblem on upper trim panel looks likde small tube with wires attached
Jan 9, 2011 at 9:23 PM