no power to hvac control
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Cruising
Joined: Jun 2009
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From: seymour tn
no power to hvac control
Hey guys! I've got a 97 coupe with no ac. The ac comes on and works perfectly when IT wants to and quits when IT wants to. I've checked fuses, relays, codes,grounds(the ones by the headlights), pulled the unit, took it apart and I can't find anything obvious. Can anyone offer any ideas? They would be so appreciated!! Thanks in advance.
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
The ignition switch. Not the lock cylinder part, but the electrical switch section. He found that part of the switch housing was either loose or not snapped together properly, causing an intermittent open circuit internally. His problem was one that came and went. Fuse #18 was dead but gets it's power through one of the sets of contacts in the switch first.
Racer
Joined: Jul 2005
Posts: 265
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From: Hamilton Ontario
Thank you - that is interesting to hear.
Since owning my '97 (going on 8 years now), periodically I will be driving, and my A/C will turn on. When it does turn on, it will always be in the Auto mode and at 23 Celsius. Or sometimes while driving with it on at say 20 Celsius, the A/C will shut off and the control unit will all of a sudden go completely black. Maybe a second later, the A/C will come back on and the control unit will light up again. However, when it does comes back on, it will be in Auto mode and at 23 Celsius!!! Additionally, sometimes the temperature readout will convert from Celsius units to Fahrenheit units. Took it to the dealer for this a few times, but unfortunately they could not duplicate the problem.
Does the above sound like it could be an ignition switch issue, or maybe even a loose wire or something in behind the A/C control unit?
Since owning my '97 (going on 8 years now), periodically I will be driving, and my A/C will turn on. When it does turn on, it will always be in the Auto mode and at 23 Celsius. Or sometimes while driving with it on at say 20 Celsius, the A/C will shut off and the control unit will all of a sudden go completely black. Maybe a second later, the A/C will come back on and the control unit will light up again. However, when it does comes back on, it will be in Auto mode and at 23 Celsius!!! Additionally, sometimes the temperature readout will convert from Celsius units to Fahrenheit units. Took it to the dealer for this a few times, but unfortunately they could not duplicate the problem.
Does the above sound like it could be an ignition switch issue, or maybe even a loose wire or something in behind the A/C control unit?
Team Owner
Joined: May 2001
Posts: 36,836
Likes: 244
From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Thank you - that is interesting to hear.
Since owning my '97 (going on 8 years now), periodically I will be driving, and my A/C will turn on. When it does turn on, it will always be in the Auto mode and at 23 Celsius. Or sometimes while driving with it on at say 20 Celsius, the A/C will shut off and the control unit will all of a sudden go completely black. Maybe a second later, the A/C will come back on and the control unit will light up again. However, when it does comes back on, it will be in Auto mode and at 23 Celsius!!! Additionally, sometimes the temperature readout will convert from Celsius units to Fahrenheit units. Took it to the dealer for this a few times, but unfortunately they could not duplicate the problem.
Does the above sound like it could be an ignition switch issue, or maybe even a loose wire or something in behind the A/C control unit?
Since owning my '97 (going on 8 years now), periodically I will be driving, and my A/C will turn on. When it does turn on, it will always be in the Auto mode and at 23 Celsius. Or sometimes while driving with it on at say 20 Celsius, the A/C will shut off and the control unit will all of a sudden go completely black. Maybe a second later, the A/C will come back on and the control unit will light up again. However, when it does comes back on, it will be in Auto mode and at 23 Celsius!!! Additionally, sometimes the temperature readout will convert from Celsius units to Fahrenheit units. Took it to the dealer for this a few times, but unfortunately they could not duplicate the problem.
Does the above sound like it could be an ignition switch issue, or maybe even a loose wire or something in behind the A/C control unit?
Last edited by LoneStarFRC; Jun 23, 2009 at 09:27 AM. Reason: typo
Racer
Joined: Jul 2005
Posts: 265
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From: Hamilton Ontario
I never knew the manual units had that problem too - I thought that it was only the dual zone versions! That is interesting!
As an aside: the last time the temperature display on the head unit switched on its own from Celsius to Fahrenheit, I just tapped on the corner of the temperature display window for the heck of it, and as soon as I did so, all the needles on the gauges of my instrument panel did the "full sweep". That is why I always wondered if there was some sort of loose wire issue happening as well.
Thanks for the info on the ignition switch - good to know. May be the next winter project.
As an aside: the last time the temperature display on the head unit switched on its own from Celsius to Fahrenheit, I just tapped on the corner of the temperature display window for the heck of it, and as soon as I did so, all the needles on the gauges of my instrument panel did the "full sweep". That is why I always wondered if there was some sort of loose wire issue happening as well.
Thanks for the info on the ignition switch - good to know. May be the next winter project.
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Team Owner
Joined: May 2001
Posts: 36,836
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
The problem he was having was not the HVAC unit at all, it was an ignition switch problem. Also, the C60 system experiences far fewer problems than the CJ2 as far as the controls and actuators, etc.
Last edited by LoneStarFRC; Jun 23, 2009 at 09:26 AM. Reason: typos; ugh
Thread Starter
Cruising
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From: seymour tn
Damo97,
sorry I'm just now getting back to you...the ignition switch doesn't have to wait til winter.It's easy to pull and to have a look at it. LoneStarFRC really saved me from pulling my hair out! He knows these cars.
Anyway, there's a green plastic cover on the back of the switch. Under that cover is a couple of metal contacts. One of mine was loose...I squeezed the tabs on it, put it back together and it works great!!!
sorry I'm just now getting back to you...the ignition switch doesn't have to wait til winter.It's easy to pull and to have a look at it. LoneStarFRC really saved me from pulling my hair out! He knows these cars.
Anyway, there's a green plastic cover on the back of the switch. Under that cover is a couple of metal contacts. One of mine was loose...I squeezed the tabs on it, put it back together and it works great!!!
