Climate Control Issue
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From: Derry nh
Climate Control Issue
My '91's climate control started acting up recently. Seems to cool normally but heat won't really start to come on unless I set to 90 deg (max heat). Then it gets really hot and I have to turn it down. Any setting from 70 to 85 doesn't seem to change the heat output.
Used to work fine (could notice changes in heat output between 70 and 85) until I replaced the CDM radio receiver (several times, since the repair shop couldn't fix it on then first or second attempt). I think some of the climate control relays are behind the CDM. Likely I could have disturbed something but hate to take that mess apart yet again.
Used to work fine (could notice changes in heat output between 70 and 85) until I replaced the CDM radio receiver (several times, since the repair shop couldn't fix it on then first or second attempt). I think some of the climate control relays are behind the CDM. Likely I could have disturbed something but hate to take that mess apart yet again.
Race Director
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Instructor
Joined: Jun 2004
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From: Derry nh
THanks... Does engine temperature matter when I get the numbers? WHat are good/bad numbers I should expect to see?
BTW, there are no codes in the -00 System Faults although on occasion the LED above one of the buttons will start blinking. Need to remember to check the -00 System Faults then as it appears it doesn't keep a fault history.
BTW, there are no codes in the -00 System Faults although on occasion the LED above one of the buttons will start blinking. Need to remember to check the -00 System Faults then as it appears it doesn't keep a fault history.
Le Mans Master
Joined: Dec 2000
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From: San Diego, Ca
Do see what the numbers show - though correlated (somewhat) to temperature - it isn't always exact -the important thing is that the numbers for the Temperature Door change as the Temp Sensors change.
Controls communicate over serial data lines with the Programmer which is the Processor. To achieve the temperature dialed in from the Controls, the Programmer relies on input from the outside and inside Temp Sensors EXCEPT at "60" and "90". At these inputs, the Temperature Door is moved to full cold or full hot and the Sensors are ignored; so, when you look at these extremes, they should indicate full open/close for the Door. At anything in between, the numbers should change. And they will probably continue to change until the Indoor Temp Sensor returns something close to whatever has been dialed in from the Controls and at that point, the door position will remain somewhat steady.
If the numbers are changing but the vent temperature doesn't change (you might check it with a digital thermometer), I'd suspect the Temp Door isn't moving. More often than not, the motor gear that drives it is stripped.
If nothing is changing, that's either a communication problem or the Programmer is whacked and the easiest way to check it is with a Bi-directional scanner. The scanner will emulate the Controls and if it's starts working, the Controls are at fault. If it doesn't it's the Programmer.
Controls communicate over serial data lines with the Programmer which is the Processor. To achieve the temperature dialed in from the Controls, the Programmer relies on input from the outside and inside Temp Sensors EXCEPT at "60" and "90". At these inputs, the Temperature Door is moved to full cold or full hot and the Sensors are ignored; so, when you look at these extremes, they should indicate full open/close for the Door. At anything in between, the numbers should change. And they will probably continue to change until the Indoor Temp Sensor returns something close to whatever has been dialed in from the Controls and at that point, the door position will remain somewhat steady.
If the numbers are changing but the vent temperature doesn't change (you might check it with a digital thermometer), I'd suspect the Temp Door isn't moving. More often than not, the motor gear that drives it is stripped.
If nothing is changing, that's either a communication problem or the Programmer is whacked and the easiest way to check it is with a Bi-directional scanner. The scanner will emulate the Controls and if it's starts working, the Controls are at fault. If it doesn't it's the Programmer.
