ELECTRICAL TROUBLESHOOTING - continued - TM-9-2320-386-24-1-10105

TM 9-2320-386-24-1-1

0012 00

Electrical Troubleshooting (Contd)

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

Step 3. Touch negative lead to pin 1 of air dryer heater connector and positive lead to pin 2 of

air dryer heater connector.

a. If continuity is found, go to test 2.

b. If continuity is not found, it may be necessary to remove air dryer heater and

recheck after being cooled to 53F (12C) before replacing air dryer heater

Test 2. Check for continuity of ground lead.

Step 1. Touch negative lead of multimeter to ground at crossmember and positive lead to pin 1

of harness plug.

a. If continuity is found, go to test 3.

b. If continuity is not found, replace ground lead.

Test 3. Check for voltage at air dryer heater connector.

Step 1. Set multimeter to a voltage range that will measure 24 Vdc.

Step 2. Turn accessory/battery switch to ON position.

Step 3. Touch negative lead of multimeter to ground and positive lead to pin 2 of harness plug.

a. If voltage is found, replace air dryer heater (WP 0281 00).

b. If voltage is not found, go to test 4.

Test 4. Check for voltage at connector.

Step 1. Disconnect lead 27 from connector.

Step 2. Touch negative lead to ground and positive lead to connector.

a. If voltage is found, replace lead 27 from connector to air dryer heater (WP 0281 00).

b. If voltage is not found, go to test 5.

Test 5. Test for voltage at front-to-rear harness connector.

Step 1. Disconnect rear harness from front harness.

Step 2. Turn accessory/battery switch to ON position.

Step 3. Touch negative lead of multimeter to ground and positive lead to pin F of front harness

receptacle.

a. If voltage is found, replace lead 27 to connector (WP 0125 00).

b. If voltage is not found, perform step 2, test 5 to check accessory/battery switch

operation.

END OF TESTING!

PERSONNEL HEATERS

26. PERSONNEL HOT WATER HEATER DOES NOT OPERATE OR DOES NOT OPERATE IN HIGH

OR LOW POSITION

Test 1. Check heater high/low switch for power input.

Step 1. Set multimeter to a range that will measure 24 Vdc.

Step 2. Disconnect lead 400 at rear of heater switch.

Step 3. Touch multimeter positive lead to contact end of lead 400 at heater switch.

Step 4. Touch multimeter negative lead to frame ground. Voltage should be present.

a. If voltage is present, go to test 2.

b. If voltage is not present, replace or repair lead 400 (WP 0125 00).