Test Step 5. Check the Voltage at the Lamp for the Air Inlet Heater

158

TM 9-2320-312-24-2

Troubleshooting Section

No Reinstall the lamp for the air inlet heater.

Expected Result:

Proceed to Test Step 9.

The test lamp turns on and the test lamp turns off

Test Step 6. Check the Wiring for the Air

with the "Intake Air Heater Enable Test".

Inlet Heater

Results:

A. Turn the ignition key switch to the OFF position.

Yes

B. Disconnect both wires from the air inlet heater.

Repair: Replace the air inlet heater and rerun the

test. Verify that the original problem has been

C. Use a multimeter to measure the resistance

resolved.

between the two ends of the wire that connects

the air inlet heater to the air inlet heater relay.

STOP.

D. Measure the resistance from the engine ground

stud to the other end of the wire for the air inlet

heater that connects to the ground stud.

Repair: The connector P501 for the air inlet heater

relay is not receiving the correct voltage.

Expected Result:

Proceed to Test Step 8.

The measured resistance is less than 20 Ohms.

Test Step 5. Check the Voltage at the

Results:

Lamp for the Air Inlet Heater

Yes

A. Turn the ignition key switch to the OFF position.

Repair: Replace the air inlet heater. Verify that the

problem is resolved.

B. Locate the lamp in the dash for the air inlet

heater. Remove the lamp from the dash.

STOP.

C. Connect a voltage test lamp between the two

terminals of the lamp socket.

D. Turn the ignition key switch to the ON position.

Repair: Repair the damaged wire. Verify that the

problem is resolved.

E. Go to the "Intake Air Heater Enable Test" on the

electronic service tool.

STOP.

Test Step 7. Check the Relay Contact at

F. Start the test and watch the voltage test lamp.

the +Battery Terminal Connection.

Note: Do not leave the "Intake Air Heater Enable

Test" on. Avoid unnecessary cycling of the air

A. Turn the ignition key switch to the OFF position.

inlet heater in order to prevent the battery from

discharging. The "Intake Air Heater Enable Test"

has a one minute timer in order to disable the test

when the time expires.

Expected Result:

The test lamp turns on and the test lamp turns off

with the "Intake Air Heater Enable Test".

Results:

Yes

Repair: Replace the lamp for the air inlet heater.

Verify that the problem has been resolved.

STOP.