M: EATC HEATER BLOWER MOTOR DOES NOT OPERATE AT HIGH SPEED

PINPOINT TEST M: EATC HEATER BLOWER MOTOR DOES NOT OPERATE AT HIGH SPEED

M1 CHECK BLOWER MOTOR HI SPEED OPERATION

- Start engine, select MAX A/C and position the blower thumbwheel to a position midway between LO and HI. Verify that the blower motor operates. Then, rotate the blower thumbwheel to HI and check to see if the blower speed responds to the thumbwheel movement.

- Does the blower speed increase with movement of the thumbwheel toward HI?

- Yes
Perform Pinpoint Test A.

- No
Go to M2.

F2 CHECK FOR 10 VOLTS OR MORE

- With ignition switch OFF, disconnect the harness connector from the A/C blower motor speed control.
- Start engine, select MAX A/C and rotate the blower thumbwheel to HI. Check voltage between Pins 1 and 2 of disconnected harness connector. Voltage reading should be 10 or more volts.

- Is voltage 10 volts or more?

- Yes
Replace A/C blower motor speed control . Restore vehicle. Retest system.

- No
Go to M3.

M3 VOLTAGE CHECK AT PIN 9 OF EATC

- Reconnect harness connector to A/C blower motor speed control.
- Start engine, select MAX A/C and rotate blower thumbwheel to HI. Measure voltage between Pin 9 of the EATC control assembly and ground. Must indicate 10 or more volts when the blower thumbwheel is rotated to the stop at HI.

- Is voltage 10 volts or greater?

- Yes
Service Circuit 758 (P/W) for Town Car or Circuit 754 (LG/W) for Crown Victoria, Grand Marquis between Pin 9 of EATC control assembly and Pin 3 of A/C blower motor speed controller. Restore vehicle. Retest system.

- No
Replace EATC control assembly. Restore vehicle. Retest system.