Symptom  | Procedure  | 
|---|---|
| 
 Important: If you disconnect either side high beam headlamp with ignition On, headlamps will not operate when you reconnect the connector until you cycle the key.  | |
Low beam headlamps inoperative, high beam OK.  | Disconnect headlamp/turn switch connector. Probe cavity 5 circuit 1201 with a test light-to-ground. Does lamp light? If yes, faulty headlamp/turn switch. If no, open circuit 1201.  | 
High beam headlamps inoperative, low beam OK.  | Disconnect headlamp/turn switch connector. Probe cavity 7 circuit 1200 with a test light-to-ground. Does lamp light? If yes, faulty headlamp/turn switch. If no, open circuit 1200.  | 
High and low beam headlamps inoperative.  | Check circuit 550 at headlamp switch for an open. If OK, faulty headlamp switch.  | 
High beam indicator does not operate.  | Cluster test using Tech 2. If High beam indicator does not work with cluster test, faulty cluster. Refer to I/P section of this service manual.  | 
Right high beam headlamp, DRL, inoperative.  | Check right high beam headlamp for open element. If OK, check for open 593 or 1200 circuit.  | 
Left high beam headlamp, DRL, inoperative.  | Check left high beam headlamp for open element. If OK, check for open circuit 40 or open circuit 1200.  | 
DRL Inoperative:  | |
DTC B2600  | Chart 1  | 
DTC B2602  | Chart 2  | 
DTC B2603  | Chart 3  | 
DRL On with headlamp switch On, dimmer switch in low position.  | Using Scan tool, observe high beam input. If voltage is between 6-8 volts, disconnect BCM connector J3 (PNK 24 way) using a DVOM, check CKT 592, Green wire for short to ground. If OK, faulty BCM.  | 
DRL inoperative, high beam indicator On with headlamp switch in any position.  | Disconnect BCM connector J1. Probe circuit 1200 with a test light to B+. Turn the headlamp switch On, dimmer switch in the high beam position. Does lamp light? If no, open circuit 1200. If yes, faulty connection or BCM.  | 
DRL lamps do not turn Off with park brake applied.  | Disconnect BCM connector J2. Probe circuit 1134 with a test light to B+. Apply parking brake. Does lamp light? If no, open circuit 1134. If yes, faulty connection or BCM.  |