Courtesy Lamps Always On. Chevrolet Chevy C Cab/Chassis HD (GMT 400) 2001

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 2001 🢒 Chevy C Cab/Chassis HD (GMT 400) 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Courtesy Lamps Always On

Step

Action

Yes

Schematic Reference: Interior Lights Schematics

Did you perform the courtesy lamp operation and perform the necessary inspections?

Go to Step 2

Go to Interior Lighting Systems Description and Operation

Close all the doors.
Turn OFF the dome lamp switch.

Do the courtesy lamps turn OFF?

Go to Testing for Electrical Intermittents

Go to Step 3

Turn ON the dome override switch.

Are the courtesy lamps still illuminated?

Go to Step 4

Go to Step 5

Turn OFF the dome override switch.
Disconnect the door jamb switches one at a time, checking to see if the courtesy lamps turn off after each disconnect.

Do the courtesy lamps turn off after a disconnect?

Go to Step 10

Go to Step 8

Disconnect the headlamp switch.

Are the courtesy lamps still illuminated?

Go to Step 6

Go to Step 11

•	If equipped with remote keyless entry (RKE), disconnect the keyless entry module.

•	If equipped without RKE, disconnect the interior lighting module.

Are the courtesy lamps illuminated?

Go to Step 9

Go to Step 7

Test the interior lamp control circuit of the headlamp switch for a short to ground.

Did you find and correct the condition?

Go to Step 16

Go to Step 12

Repair the short to ground in the interior lamp defeat switch signal circuit.

Did you complete the repair?

Go to Step 16

Repair the short to ground in the courtesy lamp low control circuit.

Did you complete the repair?

Go to Step 16

Inspect for poor connections at the harness connector of the headlamp switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Inspect for poor connections at the harness connector of the switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Inspect for poor connections at the harness connector of the keyless entry module or the interior lighting module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Replace the switch. Refer to Door Jamb Switch Replacement in Doors.

Did you complete the replacement?

Go to Step 16

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Did you complete the replacement?

Step 16

•	If equipped with RKE, replace the keyless entry module. Refer to Remote Control Door Lock Receiver Replacement in Keyless Entry.

•	If equipped without RKE, replace the interior lighting module. Refer to Interior Lamp Control Module Replacement .

Did you complete the replacement?

Go to Step 16

Operate the system in order to verify the repair.

Did you correct the condition?

Go to Step 3