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Headlamps Inoperative - High Beams

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2004 Oldsmobile Bravada, 2004 GMC Envoy XUV, 2004 GMC Envoy XL, 2004 GMC Envoy, and 2004 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
Headlamps Inoperative - High Beams Diagnostic Test

Step Action Yes No
Schematic Reference:  Headlights/Daytime Running Lights (DRL) Schematics  
Connector End View Reference:  Lighting Systems Connector End Views   or  Body Control System Connector End Views  in Body Control System
1 Did you perform the Lighting Systems Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Lighting Systems 
2 Verify that the high beam headlamps are inoperative.
Do the high beam headlamps operate normally?		 Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems Go to Step 3 
3 Is only one high beam headlamp inoperative? Go to Step 4  Go to Step 5 
4
  1. Inspect the inoperative bulb for an open filament and connector for poor terminal contact and replace/repair as necessary. Refer to Headlamp Bulb Replacement (TrailBlazer) Headlamp Bulb Replacement (Bravada, Envoy, Envoy XUV, Rainier)  or Wiring Repairs in Wiring Systems.
  2. If no problem is found, repair the open, high resistance or short to ground in the high beam headlamp supply voltage circuit or ground circuit to the inoperative lamp. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you complete the repair?		 Go to Step 13  -
5 Test the headlamp dimmer switch signal and ground circuits for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct a condition?		 Go to Step 13  Go to Step 6 
6
  1. Place the headlamp switch in the HEAD position.
  2. Connect a fused jumper from ground to the headlamp dimmer switch signal terminal of the headlamp dimmer switch connector.
Do the high beam headlamps illuminate?		 Go to Step 8  Go to Step 7 
7 Connect a fused jumper from ground to the high beam headlamp relay control circuit terminal at the high beam headlamp relay in the underhood fuse block.
Do the high beam headlamps illuminate?		 Go to Step 9  Go to Step 11 
8 Inspect for poor connections at the harness connector of the headlamp dimmer switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 13  Go to Step 12 
9 Inspect for poor connections at the harness connector of the Body Control Module (BCM). Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 13  Go to Step 10 
10
IMPORTANT: Perform the setup procedure for the BCM.
Replace the body control module (BCM). Refer to Body Control Module Replacement in Body Control System.Did you complete the replacement?		 Go to Step 13  -
11 Replace the high beam headlamp relay. Refer to Relay Replacement (Within an Electrical Center)Relay Replacement (Attached to Wire Harness) in Wiring Systems.
Did you complete the repair?		 Go to Step 13  -
12 Replace the headlamp dimmer switch. Refer to Multifunction, Turn Signal Switch Replacement in Steering Wheel and Column.
Did you complete the repair?		 Go to Step 13  -
13 Operate the system in order to verify the repair.
Did you correct the condition?		 System OK Go to Step 3 
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