8206noco.fm Page 207 Thursday, July 2, 1998 1:19 PM
SYMPTOM RELATED DIAGNOSTICS ON/OFF FAN CONTROL VERBAL COMPLAINT (continued) Test 39 Checking for correct plumbing of the solenoid 1. Tighten the air supply line. 2. Remove the vent cap or vent line from the solenoid.
5. Connect the serial link jumper into the serial communication port. 6. Measure the voltage from J1B connector pin Y2 (the Auxiliary No. 1 output line) to a good ground.
If 12 volts are present, proceed to Test 128.
If air flows out of the vent, the solenoid is plumbed incorrectly. Reverse the vent and air supply lines on the solenoid and retest the fan drive.
If 12 volts are not present, proceed to Test 129.
If air does not flow out of the vent, the solenoid is defective. Repair or replace the solenoid and retest the fan drive.
Checking override switch operation
Test 128
Test 64 Checking for 12 volts at the V-MAC II module
Figure 328 — Voltage between Pin Y2 and Ground
If a manual override switch used, set the switch to the ON or override position.
Figure 327 — Voltage from Pin Y2 to Ground
1. Turn the ignition key to the OFF position.
If a manual override switch is not used, proceed to Test 256. 1. Measure the voltage from J1B connector pin Y2 (the Auxiliary No. 1 output line) to a good ground.
2. Reconnect the harness to the freon fan pressure switch.
If 12 volts are present, proceed to Test 257.
3. Disconnect the J1B connector from the V-MAC II module.
If 12 volts are not present, turn the override switch to the OFF position, proceed to Test 256.
4. If there is an override switch on the dash, turn it to the OFF or normal operation position.
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