Schematic Reference: Upfitter Provision Schematics in Wiring Systems

Connector End View Reference: Lighting Systems Connector End Views

Did you perform the Lighting Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

Verify that the roof beacon lamp is inoperative.

Does the roof beacon lamp operate normally?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

1. Place the roof beacon switch in the ON position.
2. Connect a test lamp between the power and ground circuits of the roof beacon lamp connector.

Does the test lamp illuminate?

Go to Step 8

Go to Step 4

Test the ground circuit of the roof beacon lamp for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 5

1. Remove the roof beacon switch.
2. Place a fused jumper between the hazard switch signal and battery positive voltage circuits of the roof beacon switch connector terminals.

Does the roof beacon lamp illuminate?

Go to Step 9

Go to Step 6

Test the following circuits for a high resistance, open or a short to ground:

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 7

Test the ground circuit of the roof beacon relay for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 10

Replace the bulb or lamp assembly. Refer to upfitter instructions.

Did you complete the replacement?

Go to Step 11

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Replace the roof beacon switch.

Did you complete the replacement?

Go to Step 11

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Replace the roof beacon relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the replacement?

Go to Step 11

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3