BLOWER MOTOR SYSTEM TEST
Check circuit breaker in fuse block. If circuit breaker is okay (button in), go to next step. If circuit breaker has tripped (button out), reset circuit breaker and test blower operation in all 4 speeds. If circuit breaker button pops out again, check for short circuit in system.
Turn ignition off. Disconnect blower motor connector. Locate and disconnect interior fuse panel connector. Measure resistance between Dark Blue/White wire and ground. If reading is less than 5 ohms, Dark Blue/White wire is shorted to ground. Repair Dark Blue/White wire as necessary. If reading is more than 5 ohms, go to next step.
Turn ignition on, and place blower fan switch in position No. 4. See Fig. 1. Using a voltmeter, backprobe blower motor connector (Dark Blue wire) for battery voltage. If reading is more than 10 volts, go to next step. If reading is less than 10 volts, check for open in Dark Blue wire from fuse block to blower motor.
Turn ignition off. Place blower fan switch in position No. 4. Disconnect electrical connector at blower motor. Apply 12 volts to Dark Blue wire terminal on blower motor, and ground Dark Blue/Black wire terminal on blower motor. If blower motor operates, go to next step. If blower motor does not operate, replace motor.
Disconnect blower motor resistor connector, located in blower motor housing. Using an ohmmeter, check continuity in wire between resistor and blower motor connector. If reading is less than 5 ohms, go to next step. If reading is more than 5 ohms, repair Dark Blue/Black wire.
Reconnect resistor connector. Measure resistance between Dark Blue/Black wire and specified wires. See BLOWER MOTOR RESISTOR TEST table. If readings are as specified, go to next step. If readings are not as specified, replace blower resistor.
BLOWER MOTOR RESISTOR TEST
Measure resistance on Dark Blue/Yellow, Dark Blue, Dark Blue/Red and Dark Blue/White wires between blower resistor and blower switch. If readings on all wires are less than 5 ohms, go to next step. If reading on any wire exceeds 5 ohms, repair wire in question.
Measure resistance between Black wire in blower switch connector and chassis ground. If reading is less than 5 ohms, go to next step. If reading is more than 5 ohms, repair open circuit in Black wire or poor ground connection.
Using an ohmmeter, check blower switch resistance between Black wire and specified wires at blower resistor connector. See BLOWER SWITCH CONTINUITY TEST table. If blower switch resistance is not as specified, replace blower switch. If blower switch resistance is as specified, test is complete.
BLOWER SWITCH CONTINUITY TEST
Switch Position/Wire Color/Ohms
OFF/AllMore Than 10,000
1DK BLU/YEL. Less Than 5
1Except DK BLU/YEL. More Than 10,000
2DK BLU. Less Than 5
2Except DK BLU. More Than 10,000
3DK BLU/RED. Less Than 5
3Except DK BLU/RED. More Than 10,000
4DK BLU/WHT. Less Than 5
4Except DK BLU/WHT. More Than 10,000
Saturday, November 22nd, 2008 AT 6:59 AM