a/c control head 86-89
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a/c control head 86-89
I posted to the parts wanted for an a/c control head for '89. Getting a reading of 8 volts on the green wire and my tech says needs replacement. Found 1 in Ft. Lauderdale, real pricey and with exchange which indicates to me that he has the means to repair or have repaired. Anyone possibly have info on repairing or possibly the part #? Green wire supposed to read 0 volts. The voltage took out my servo motor(or vice versa) but have a servo replacement that does work. Thanks in advance.
Jim
Jim
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I don't know what you mean - there are several green wires - one of which is the compressor ground circuit which (electronic air) runs to the Blower Control Module and it's going to have voltage until grounded by the Module. If the Module isn't grounding it, there are specific diagnostic procedures, but it's usually because there's no gas. If you can provide a few more details about your issue, maybe we can help out.
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Sorry, I'll try to clarify a little better. Original problem was with the blend door, which is controlled by an actuator motor and that was "thought" to be the problem. When the control panel was in heat mode, nothing happened. All other functions on the panel worked. (Think the term a/c control head, which is the proper term for the c68 system might have thrown you off) When my mechanic did ohms, voltage, etc. tests with ignition switch on, a/c set to 70 degrees as per display and the voltage to terminal B is incorrect, (as per my 8 volt reading) this should read 0, instructions say replace a/c control head. I believe their is a resistor or some other malfunction in the circuit board allowing voltage to this control when there shouldn't be. Also believe this took out my actuator motor somewhere along the line. Really hate having to try and find a used controller head but prefer finding someone to trouble shoot the board for this 50 cent part, but I will continue to look.
Jim
Jim
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Disconnect and reconnect the battery to clear memory/any glitches. When the system powers back up, the door should move from through it's full range and nothing else should work. This is how it learns door position and the process can take a minute or two. When done, Blower and everything else should be functional.
Battery voltage is applied to the motor and reversed to change direction.
The Feedback Circuit is a 5 volt reference with a range of 0 to 5 volts and that's what you should see if manually move the Door.
Make sure the plastic link connecting the motor to the door linkage is intact.
Sounds like you may need a Programmer - above and to the right of the accelerator - though some have had luck taking it apart and replacing resistors or other parts. Control Panel is probably ok if it responds/lights up correctly when you push the buttons.
Battery voltage is applied to the motor and reversed to change direction.
The Feedback Circuit is a 5 volt reference with a range of 0 to 5 volts and that's what you should see if manually move the Door.
Make sure the plastic link connecting the motor to the door linkage is intact.
Sounds like you may need a Programmer - above and to the right of the accelerator - though some have had luck taking it apart and replacing resistors or other parts. Control Panel is probably ok if it responds/lights up correctly when you push the buttons.
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Thanks for the info. I will pass this along to my tech. I would hate to try and find parts one at a time. gets a little pricey as you well know. I will keep you and everyone else who experiences this, (these) problems.
Jim
Jim
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From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
Try 20th street auto in arizona. They have maybe 50 C4's in the yard at all times. They have an old guy named John that squirrels away thing like perfect working programmers and panels and stuff.
