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 221 of 1207

TM 9-2320-361-20

Table 2-4. Electrical Troubleshooting (Contd).

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

HEATING SYSTEMS

39. ENGINE MANIFOLD HEATER DOES NOT WORK

Test 1. Test engine manifold heater ignition circuit for battery voltage.

Step 1. Disconnect lead 55 from engine manifold heater ignition unit. Manifold heater fuel pump is

now disabled.

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

Step 3. Turn accessory/ignition switch to ON position.

Step 4. Push manifold heater switch and hold.

Step 5. Touch positive lead of multimeter to contact end of lead 55 and negative lead to frame

ground.

a. If battery voltage is present, go to test 4.

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

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