TM-9-2320-361-20

2-1/2-TON, 6x6, M44A2 SERIES TRUCKS (MULTIFUEL)

TECHNICAL MANUAL; UNIT MAINTENANCE

OCTOBER 1991

TM-9-2320-361-20 - Page 231 of 1207

TM 9-2320-361-20

Table 2-4. Electrical Troubleshooting (Contd).

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

42. HEATER CONTROL BOX LIGHT INOPERATIVE, BUT HEATER OPERATIVE

Test 1. Check for voltage at heater control box indicator lamp.

Step 1.

Step 2.

Step 3.

Step 4.

Step 5.

Step 6.

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

Position heater control switch to RUN.

Position heater switch to HIGH.

Remove heater control box indicator lamp.

Touch positive lead of multimeter to indicator lamp socket.

Touch negative lead of multimeter to frame ground.

a. If voltage is present, replace indicator lamp.

b. If voltage is not present, go to test 2.

Test 2. Check for voltage between personnel heater and heater control box.

Step 1. Disconnect wiring harness at personnel heater.

Step 2. Connect jumper wire from pin D to pin E at personnel heater.

a. If heater control box indicator lamp is lit, replace personnel heater (para. 14-2).

b. If indicator lamp fails to light, replace or repair wiring harness (para. 4-51).

TRAILER CONNECTION SYSTEM

43. ONE OR MORE TRAILER LIGHTS INOPERATIVE

Test 1. Test trailer receptacle voltage.

Step 1. Turn main light switch lever to position corresponding to inoperative lamp.

NOTE

For stoplight circuit test, brake pedal must be depressed and air

pressure maintained.

Step 2. Set multimeter to a voltage range that will measure 24 Vdc.

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