Does this sound like A/C control head ('95 w/ electronic A/C)?
09-28-2005, 06:58 PM
#1
Le Mans Master
Thread Starter
Does this sound like A/C control head ('95 w/ electronic A/C)?
Well as luck would have it, w/ my '95 in a "for sale" status (sort of, not advertised heavily due to fuel prices) the automatic climate control is acting up. Here's the symptoms:
Won't let you adjust interior temperature (thermostat) down, only up to higher temp. No amount of pressing the rocker switch on the left to reduce the temp setting for the thermostat would have any effect, but pressing the right end of the rocker would increment the temp as per normal operation. Plugged and unplugged fuses for the A/C module and A/C program in hopes it would reset something-- no help. BUT, when I pulled battery negative cable to kill juice to entire car, it reversed the problem! After reconnecting battery neg cable the rocker switch behaved in the inverse: now it will allow me to decrease the temp but won't allow the temp to be increased.
The fact that it changed, went inverse, after pulling battery juice tells me it is probably the A/C control module and not the keypad circuit board directly behind the buttons (which cleaning the keypad board often fixes glitchy button problems).
I'm going to have to fix this before the car goes to anyone else.
I can research A/C control module repair/replace procedure using the forum search, so not asking for that yet, just looking for a confirmation of my suspicion regarding the A/C control module being the culprit behind this thermostat rocker switch glitch.
Won't let you adjust interior temperature (thermostat) down, only up to higher temp. No amount of pressing the rocker switch on the left to reduce the temp setting for the thermostat would have any effect, but pressing the right end of the rocker would increment the temp as per normal operation. Plugged and unplugged fuses for the A/C module and A/C program in hopes it would reset something-- no help. BUT, when I pulled battery negative cable to kill juice to entire car, it reversed the problem! After reconnecting battery neg cable the rocker switch behaved in the inverse: now it will allow me to decrease the temp but won't allow the temp to be increased.
The fact that it changed, went inverse, after pulling battery juice tells me it is probably the A/C control module and not the keypad circuit board directly behind the buttons (which cleaning the keypad board often fixes glitchy button problems).
I'm going to have to fix this before the car goes to anyone else.
I can research A/C control module repair/replace procedure using the forum search, so not asking for that yet, just looking for a confirmation of my suspicion regarding the A/C control module being the culprit behind this thermostat rocker switch glitch.
09-28-2005, 11:27 PM
#2
Drifting
Member Since: Sep 2003
Location: 1994 LT1 Coupe 6-speed with FX3 & 2000 LS1 Vert 6-Speed with F45 Hunterdon County, NJ
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Lone Ranger,
Our 94 LT1 acted similar to yours when we first got it, sometimes it wouldn't go up, other times it wouldn't go down.
However, I do not remember if it ever changed after a battery disconnect, but your battery disconnect may have just been coincidental and not the cause of the 'switch' from up to down.
On ours, after removing the control head rubber membrane and cleaning its carbon buttons and the circuit board contact points (with a pencil eraser), it has worked fine now for 2+ years.
If you have never disassembled the console/dash before, I would offer a couple of suggestions:
1. When you remove the console lid, carefully pull out the lid light wire until you retrieve the plug, which can be disconnected to totally move the lid out of the way.
2. Do remove the shifter **** so you can completely remove the console cover and not damage the soft rubber coating.
3. Take your time and be sure to check the manual to find all the screws to the upper console cover.
Good Luck and I hope this helped.
Our 94 LT1 acted similar to yours when we first got it, sometimes it wouldn't go up, other times it wouldn't go down.
However, I do not remember if it ever changed after a battery disconnect, but your battery disconnect may have just been coincidental and not the cause of the 'switch' from up to down.
On ours, after removing the control head rubber membrane and cleaning its carbon buttons and the circuit board contact points (with a pencil eraser), it has worked fine now for 2+ years.
If you have never disassembled the console/dash before, I would offer a couple of suggestions:
1. When you remove the console lid, carefully pull out the lid light wire until you retrieve the plug, which can be disconnected to totally move the lid out of the way.
2. Do remove the shifter **** so you can completely remove the console cover and not damage the soft rubber coating.
3. Take your time and be sure to check the manual to find all the screws to the upper console cover.
Good Luck and I hope this helped.
09-30-2005, 02:21 PM
#4
Racer
Member Since: May 2005
Location: houston texas
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Originally Posted by Lone Ranger
Well as luck would have it, w/ my '95 in a "for sale" status (sort of, not advertised heavily due to fuel prices) the automatic climate control is acting up. Here's the symptoms:
Won't let you adjust interior temperature (thermostat) down, only up to higher temp. No amount of pressing the rocker switch on the left to reduce the temp setting for the thermostat would have any effect, but pressing the right end of the rocker would increment the temp as per normal operation. Plugged and unplugged fuses for the A/C module and A/C program in hopes it would reset something-- no help. BUT, when I pulled battery negative cable to kill juice to entire car, it reversed the problem! After reconnecting battery neg cable the rocker switch behaved in the inverse: now it will allow me to decrease the temp but won't allow the temp to be increased.
The fact that it changed, went inverse, after pulling battery juice tells me it is probably the A/C control module and not the keypad circuit board directly behind the buttons (which cleaning the keypad board often fixes glitchy button problems).
I'm going to have to fix this before the car goes to anyone else.
I can research A/C control module repair/replace procedure using the forum search, so not asking for that yet, just looking for a confirmation of my suspicion regarding the A/C control module being the culprit behind this thermostat rocker switch glitch.
Won't let you adjust interior temperature (thermostat) down, only up to higher temp. No amount of pressing the rocker switch on the left to reduce the temp setting for the thermostat would have any effect, but pressing the right end of the rocker would increment the temp as per normal operation. Plugged and unplugged fuses for the A/C module and A/C program in hopes it would reset something-- no help. BUT, when I pulled battery negative cable to kill juice to entire car, it reversed the problem! After reconnecting battery neg cable the rocker switch behaved in the inverse: now it will allow me to decrease the temp but won't allow the temp to be increased.
The fact that it changed, went inverse, after pulling battery juice tells me it is probably the A/C control module and not the keypad circuit board directly behind the buttons (which cleaning the keypad board often fixes glitchy button problems).
I'm going to have to fix this before the car goes to anyone else.
I can research A/C control module repair/replace procedure using the forum search, so not asking for that yet, just looking for a confirmation of my suspicion regarding the A/C control module being the culprit behind this thermostat rocker switch glitch.
10-12-2005, 12:52 AM
#5
Navigator
Member Since: Aug 2005
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Same problem on my 96 LT4 Climate Control
Your description of UP button working sometimes and DOWN button working other times (as well as intermittent operation of other buttons) is identical to my experience. It appears to change from one set of working buttons to a different set of working buttons when the ignition is turned off and back on. Occasionally all buttons work fine. These changing symtoms seem to indicate that the problem is not in the front panel, but rather in a connection or possibly in a solid state component (perhaps a timing issue) on the circuit board inside the control box. Cleaning the front panel contacts may disturb a bad connection sufficiently to make contact again and cause all buttons to work (at least temporarily).
I would love to know if anyone has tracked this rather unique problem to the source. It would sure save me the headache of trying to track it down.
I would love to know if anyone has tracked this rather unique problem to the source. It would sure save me the headache of trying to track it down.
