Part 2 of 2

Chart C-10, Part 2 of 2.:

Chart C-10 Wiring Diagram:

CIRCUIT DESCRIPTION:


The A/C relay is ECM controlled to delay A/C clutch engagement 0.3 seconds after A/C is turned "ON." This allows the IAC to adjust engine speed before the A/C clutch engages. The ECM also causes the relay to disengage the A/C clutch during WOT operation. The A/C relay is energized when the ECM provides a ground path for CKT 366.


TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.

1. Checks for battery voltage to the A/C compressor relay through CKT 67.

2. Substitutes for relay to determine if problem is in relay or in CKT 59, A/C clutch coil, or ground.

3. Checks for open in CKT 67 to relay.

4. Checks to see that A/C "ON" signal is getting to ECM through CKT 67. A test light "OFF" at this time indicates CKT 67 is open between the cycling switch and the ECM.