3. Verify that a test lamp illuminates between the B+ circuit terminal 86 and ground.
锟斤拷 If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the
B+ circuit fuse is open, test the control circuit terminal 87 for a short to ground. If the circuit tests normal, test or replace the fog lamp
relay.
4. Verify that a test lamp illuminates between the B+ circuit terminal 30 and ground.
锟斤拷 If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
5. Disconnect the harness connector at the appropriate park lamp.
6. Test for less than 5 ohm between the park lamp ground circuit terminal and ground.
锟斤拷 If greater than the specified range, test the ground circuit for an open/high resistance.
7. Connect the harness connector at the park lamp.
8. Connect a 15 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87. Verify the park lamp is activated.
锟斤拷 If the park lamp does not activate and the circuit fuse is good, test the control circuit for an open/high resistance. If the circuit tests normal,
test or replace the park lamp.
锟斤拷 If the park lamp does not activate and the circuit fuse is open, test the control circuit for a short to ground. If the circuit tests normal, test or
replace the park lamp.
9. Connect a test lamp between the B+ circuit terminal 86 and the control circuit terminal 85.
10. Command the Parking Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded
states.
锟斤拷 If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.
锟斤拷 If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace
the BCM.
11. If all circuits test normal, test or replace the park lamp relay.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Relay Replacement (Attached to Wire Harness) (See: Power and Ground Distribution/Power Distribution Relay/Service and Repair/Relay
Replacement (Attached to Wire Harness))Relay Replacement (Within an Electrical Center) (See: Power and Ground Distribution/Power
Distribution Relay/Service and Repair/Relay Replacement (Within an Electrical Center))
* Headlamp Replacement (Cadillac Escalade) (See: Lighting and Horns/Headlamp/Service and Repair/Removal and Replacement/Headlamp
Replacement (Cadillac Escalade))Headlamp Replacement (GMC Yukon Two-mode Hybrid) (See: Lighting and Horns/Headlamp/Service
and Repair/Removal and Replacement/Headlamp Replacement (GMC Yukon Two-mode Hybrid))Headlamp Replacement (Yukon) (See:
Lighting and Horns/Headlamp/Service and Repair/Removal and Replacement/Headlamp Replacement (Yukon))Headlamp Replacement
(Chevrolet Tahoe Two-mode Hybrid) (See: Lighting and Horns/Headlamp/Service and Repair/Removal and Replacement/Headlamp
Replacement (Chevrolet Tahoe Two-mode Hybrid))Headlamp Replacement (Tahoe, Avalanche) (See: Lighting and Horns/Headlamp/Service
and Repair/Removal and Replacement/Headlamp Replacement (Tahoe, Avalanche))Headlamp Replacement (Escalade PLATINUM) (See:
Lighting and Horns/Headlamp/Service and Repair/Removal and Replacement/Headlamp Replacement (Escalade Platinum))Headlamp
Replacement (Non HID) (See: Lighting and Horns/Headlamp/Service and Repair/Removal and Replacement/Headlamp Replacement (Non
HID))
* Repeater Lamp Replacement (Escalade) (See: Lighting and Horns/Turn Signals/Turn Signal Lamp/Service and Repair/Repeater Lamp
Replacement (Escalade))
* Front Side Marker Lamp Replacement (Yukon) (See: Lighting and Horns/Marker Lamp/Service and Repair/Front Side Marker Lamp
Replacement (Yukon))Front Side Marker Lamp Replacement (Tahoe, Avalanche) (See: Lighting and Horns/Marker Lamp/Service and
Repair/Front Side Marker Lamp Replacement (Tahoe, Avalanche))
* Parking and Turn Signal Lamp Replacement (Tahoe, Avalanche) (See: Lighting and Horns/Parking Lamp/Service and Repair/Parking and
Turn Signal Lamp Replacement (Tahoe, Avalanche))Parking and Turn Signal Lamp Replacement (Yukon) (See: Lighting and Horns/Parking
Lamp/Service and Repair/Parking and Turn Signal Lamp Replacement (Yukon))
* Tail Lamp Replacement (Avalanche) (See: Lighting and Horns/Tail Lamp/Service and Repair/Tail Lamp Replacement (Avalanche))Tail
Lamp Replacement (GMC Yukon Two-Mode Hybrid) (See: Lighting and Horns/Brake Lamp/Brake Light Bulb/Service and Repair/Tail
Lamp Replacement (GMC Yukon Two-Mode Hybrid))Tail Lamp Replacement (Chevrolet Tahoe Two-Mode Hybrid) (See: Lighting and
Horns/Brake Lamp/Brake Light Bulb/Service and Repair/Tail Lamp Replacement (Chevrolet Tahoe Two-Mode Hybrid))Tail Lamp
Replacement (Cadillac) (See: Lighting and Horns/Tail Lamp/Service and Repair/Tail Lamp Replacement (Cadillac))Tail Lamp Replacement
(Tahoe, Yukon) (See: Lighting and Horns/Brake Lamp/Brake Light Bulb/Service and Repair/Tail Lamp Replacement (Tahoe/Yukon))
* Control Module References (See: Testing and Inspection/Programming and Relearning) for BCM replacement, setup, and programming
