TM-9-2320-260-20

TRUCK, 5-TON, 6X6, M809 SERIES (DIESEL)

TECHNICAL MANUAL; UNIT MAINTENANCE

APRIL 1995

TM-9-2320-260-20 - Page 220 of 1337

TM 9-2320-260-20

Table 2-4. Electrical Troubleshooting (Contd).

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

21. BLACKOUT TAILLIGHT LAMP DOES NOT LIGHT

Test 1. Test battery voltage at rear composite light.

Step 1.

Step 2.

Step 3.

Step 4.

Step 5.

Turn main light switch to OFF position.

Disconnect lead 24 at rear composite light on side of vehicle where blackout taillight has

failed.

Turn main light switch to BLACKOUT MARKER or BLACKOUT DRIVE position.

Set multimeter to a range that will measure 24 volts.

Check for battery voltage at contact end of lead 24.

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

b. If battery voltage is not present, go to malfunction 15, test 3 and check front wiring

harness pin E.

Test 2. Test continuity of filament in blackout taillight lamp.

Step 1. Set multimeter to RX1 scale.

Step

2.

Check continuity between lead 24 attached to rear composite light and frame ground.

a. Replace blackout taillight lamp if continuity is not present (para. 4-46).

b. If continuity is present, check for corroded contacts at lamp and on lead 24 connection

to rear wiring harness. Connect lead 24.

END OF TESTING!

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