It has been really hot here in Pennsylvania recently that I don't enjoy driving the car. I attempted to get the AC fixed but had a clogged condenser. I replace the drier and condenser about a year ago but never got back to the AC shop for a vacuum and R12 charge.
Avenue Motors in Allentown vacuumed and recharged the AC, but the control signal from the AC controller is not giving the signal to turn the compressor on. They jumped the compressor to make sure the pressures were good. I started to look into the problem by reading the service manual. There is an AC diagnostic port. It was a bit difficult to find and the manual does not indicate where it is adequately. The AC diagnostic port is located on the passenger left side kick panel.
Connected the meter to read the pulses
I read seven pulses from the port, but that is "omitted" according to the manual
I switched to an analog gauge to make sure it was seven pulses
Not sure how to embed that video, but it is 7 pulses.
Looking at the manual the evaporator thermistor can tell the auto a/c controller to turn the compressor off too. I measured the resistance of that thermistor and got 3200 ohms.
Foot area thermistor
Edited by tsi_tom, 07 July 2019 - 09:12 AM.