B: Elec. Door Actuator Motor Inop, Intermittent, or Improper

PINPOINT TEST B: A/C ELECTRONIC DOOR ACTUATOR MOTOR INOPERATIVE, INTERMITTENT OR IMPROPER OPERATION

B1 CHECK SYSTEM FOR TEMPERATURE CONTROL

- Start vehicle and run engine until it reaches normal operating temperature.
- Turn on MAX A/C mode.
- Turn temperature control knob to full COOL (left) and check for cool discharge air.
- Turn temperature control knob to full WARM (right) and check for warm discharge air.
- Vary temperature control knob from full WARM to full COOL.

- Did air temperature change?

- Yes
System is fully functional.

- No
Go to B2.

B2 CHECK FUSE

- Check Fuse 17 at the fuse panel.

- Is fuse good?

- Yes
Go to B3.

- No
Replace fuse. Go to B1. If fuse blows again, CHECK for shorts to ground in Circuit 247 and SERVICE as needed.

B3 MANUAL A/C ELECTRONIC DOOR ACTUATOR MOTOR SUPPLY VOLTAGE CHECK

- Disconnect A/C electronic door actuator motor connector located on the heater air plenum chamber accessed through the glove compartment opening.
- Using a test lamp, check for battery voltage between Circuit 247 and Circuit 246.

- Did test lamp illuminate?

- Yes
Go to B4.

- No
Check Circuits 247 and 246. Restore vehicle. Retest system.

B4 CONTROL HEAD POTENTIOMETER SUPPLY VOLTAGE CHECK

CAUTION: Never jumper Circuit 470 to Circuit 243. This could destroy A/C electronic door actuator electronics.

Reconnect A/C electronic door actuator motor connector at the evaporator case.

- Disconnect heater control connector from the back of the control head.

CAUTION: Never short across Circuits 470 and 243 as this could cause destructive damage.

- Using a voltmeter, check for reference voltage (approximately one to two volts less than battery voltage) between Circuits 470 and 243.

- Is the voltmeter registering one to two volts less than battery voltage?

- Yes
Go to B5.

- No
Check Circuits 470 and 243 for opens/shorts. Restore vehicle. Retest system.

B5 CONTROL HEAD POTENTIOMETER CHECK

- Disconnect and remove control head potentiometer.

- Check resistance between terminals 7 and 14.
- With potentiometer at full COOL, resistance should be 3000 ohms.
- With potentiometer at full WARM, resistance should be at 15 ohms.

- Is resistance linearly variable from COOL to WARM?

- Yes
Replace A/C electronic door actuator motor. Restore vehicle. Retest system.

- No
Replace potentiometer. Restore vehicle. Retest system.