SYMPTOM RELATED DIAGNOSTICS

ON/OFF FAN CONTROL VERBAL COMPLAINT (continued)

Test 16

Checking for proper freon fan pressure switch operation

4.Start the engine. Turn the air conditioning on HIGH with the doors open. Monitor the coolant temperature. Do not let the engine run long enough to exceed 190 °F (88°C). If the freon fan pressure switch is working properly, the fan will engage after several minutes.

If the fan engages within 5 minutes, proceed to Test 32.

If the fan does not engage within 5 minutes, replace the freon fan pressure switch. Retest to be sure the problem has been corrected.

Test 17

Checking for an open between the solenoid and the freon fan pressure switch

Never place hands near the fan or belts while the engine is running.

1.Turn the ignition key to the OFF position.

2.Connect a jumper between pin B of the pressure switch connector and pin B of the freon fan pressure switch connector.

3.Connect a jumper from pin A of the pressure switch connector to a good ground.

Coolant temperature cannot be controlled in this mode. Monitor the coolant temperature. Do not let the engine run long enough to exceed 205°F (96°C). Allow the engine to cool down if necessary.

1.Turn the ignition key to the OFF position.

2.Disconnect the engine harness from the fan clutch solenoid connector.

3.Check for continuity between pin B of the fan clutch solenoid connector and pin B of the pressure switch connector.

If there is continuity, proceed to Test 34.

If there is no continuity, the harness is open between the fan clutch solenoid connector and the freon fan pressure switch connector. Locate and repair the open. Retest to be sure the problem has been corrected.

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