LEMON Manuals: Even more car manuals for everyone
Home >> Buick >> 2004 >> Century Limited >> Repair and Diagnosis >> External Pages >> Different car >> Section 100 (Lighting Systems) >> Diagnostic Information and Procedures >> Headlamps Inoperative - High Beams

Headlamps Inoperative - High Beams

WARNING: This page is about a different car, the 2004 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.
Headlamps Inoperative - High Beams

Step Action Yes No
Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics 
Connector End View Reference: Master Electrical Component List in Wiring Systems.
1 Did you perform the Lighting System Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Lighting Systems 
2
  1. Turn ON the headlamps.
  2. Ensure that the headlamp dimmer switch is in the HIGH position.
Do the high beams illuminate?
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 14  Go to Step 4 
4 Place the headlamp dimmer switch in to the FTP position.
Do the high beam headlamps illuminate?
Go to Step 7  Go to Step 5 
5
  1. Disconnect the BCM connector C1.
  2. Connect a jumper between the headlamp high beam relay control circuit and ground.
Do the high beam headlamps illuminate?
Go to Step 9  Go to Step 6 
6
  1. Remove the high beam relay.
  2. Install a fused jumper between the battery positive voltage supply circuit and the switched high beam voltage supply circuit.
Do the high beam headlamps illuminate?
Go to Step 10  Go to Step 13 
7
  1. Reinstall the high beam relay.
  2. Disconnect the multifunction switch.
  3. Connect a jumper between the headlamp dimmer switch high beam signal circuit and ground.
Do the high beam headlamps illuminate?
Go to Step 11  Go to Step 8 
8 Test for poor connection, short to battery positive voltage or an open in the headlamp dimmer switch high beam signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 20  Go to Step 19 
9
  1. Reconnect the BCM connector C1.
  2. Disconnect the multifunction switch.
  3. Connect a jumper between the headlamp dimmer switch high beam signal circuit and ground.
Do the headlamps illuminate?
Go to Step 11  Go to Step 19 
10 Test for a short to battery positive voltage, a poor connection or an open in the headlamp high beam relay control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 20  Go to Step 12 
11 Inspect for a poor connection at the harness connector of the multifunction turn signal 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 20  Go to Step 15 
12 Inspect for a poor connection at the harness connector of the high beam relay. 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 20  Go to Step 16 
13 Inspect for a poor connection at the harness connectors of the underhood fuse block. 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 20  Go to Step 17 
14 Inspect the inoperative high beam headlamp voltage supply and ground circuit for a high resistance, short to ground, short to battery positive voltage or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 20  Go to Step 18 
15 Replace the multifunction turn signal switch. Refer to Multifunction, Turn Signal Switch Replacement in Steering Wheel and Column.
Did you complete the replacement?
Go to Step 20  Go to Step 3 
16 Replace the high beam relay. Refer to Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems.
Did you complete the replacement?
Go to Step 20  -
17 Replace the underhood fuse block. Refer to Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems.
Did you complete the repair?
Go to Step 20  -
18 Replace the inoperative high beam headlamp. Refer to Headlamp Assembly or Headlamp Bulb Replacement .
Did you complete the replacement?
Go to Step 20  -
19
IMPORTANT: Perform the setup procedure for the BCM. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System.
Replace the BCM. Refer to Body Control Module Replacement in Body Control System.
Go to Step 20  -
20 Operate the system in order to verify the repair.
Did you correct the condition?
System OK Go to Step 2