Part 3 of 3

Chart C-10B A/C Clutch Circuit, (Electronic And Dual Zone A/C):

CIRCUIT DESCRIPTION:
The A/C relay is PCM controlled. It gets battery power when the ignition is turned "ON" and is energized when the PCM completes the circuit to ground. The PCM delays A/C clutch engagement 0.4 seconds after A/C is turned "ON". This allows the IAC to adjust engine rpm before the A/C clutch engages. The PCM also causes the relay to disengage the A/C clutch during WOT operation. The PCM may apply the A/C clutch during cranking to prevent A/C slugging during start-up.

Chart C-10B, Compressor Clutch Diagnosis (3 Of 3):

TEST DESCRIPTION
Numbers below refer to circled numbers on diagnostic chart.
1. Determines whether or not the PCM is turning the A/C relay "ON" due to a false A/C request signal.
2. Isolates the problem to the A/C control head and CKTs 204 and 762 to the pressure cycling switch or CKT 67 and the PCM.
3. Checks for CKT 59 short to battery power or a faulty compressor clutch.
4. Determines whether the A/C relay is faulty or the A/C relay controll circuit (CKT 366) is shorted to ground all the time.