ONE OR MORE LIGHTS NOT WORKING (WARNING, SERVICE OR BLACKOUT DRIVE LIGHT).

TM 9-2320-279-20-1

Troubleshooting Malfunctions (Cont)

2-15. TROUBLESHOOTING INSTRUCTIONS (CONT).

Table 2-9.

Troubleshooting (Cont)

Malfunction

Test or Inspection

Corrective Action

ELECTRICAL SYSTEM (CONT)

5. ONE OR MORE LIGHTS NOT WORKING (WARNING, SERVICE OR BLACKOUT DRIVE LIGHT).

NOTE

If composite lights on vehicle are LED type, perform steps (3), (4.1), and (4.2). If LED

blackout drive light, perform step (4.3).

Step 1.

Make visual check for burned out light bulb.

Replace light bulb.

Step 2.

Check socket and/or contacts for corrosion.

Clean socket and/or contacts.

Step 3.

Check for proper ground.

Clean ground connection.

Step 4.

Turn light switch to ON and check socket for 22-28 volts.

If there is 22-28 volts, replace defective lamp or bulb.

Step 4.1. Turn light switch to ON and check for 22-28 volts at chassis wire harness connectors, wire

1008/21, connected to both rear LED composite lights.

If there is 22-28 volts, replace LED composite light (para 7-62).

Step 4.2. Turn light switch to ON and check for 22-28 volts at cab wire harness connectors,

wire 1491, connected to both front LED composite lights.

If there is 22-28 volts, replace LED composite light (para 7-62).

Step 4.3. Turn blackout drive light ON and check for 22-28 volts at chassis wire harness,

wire 679.

If there is 22-28 volts, replace LED blackout drive light (para 7-68).

Change 6