Step 
 | Action 
 | Normal Result(s) 
 | Abnormal Result(s)* 
 | 
1 
 | 
- Install the scan tool.
 
- Turn the ignition switch to the ON position.
 
- Select BCM DTC with the scan tool.
 
- Check for any stored DTCs which may have an effect on serial data
line communication.
 
- Turn ignition switch OFF.
 
- Remove the scan tool.
 
 
 | No DTCs are stored
in memory. 
 | DTC is stored in memory. Go to applicable DTC table. 
 | 
2 
 | 
- Turn the ignition switch to the ON position.
 
- Turn the I/P dimmer switch to the HIGH position.
 
- Turn the headlamp switch to the PARK position.
 
 
 | The following illumination
lamps turn on inside the passenger compartment: 
|     •  | HVAC control head faceplate. |  
  
|     •  | MEMORY, MIRRORS, DOORLOCK, and WINDOW switch faceplate. |  
  
|     •  | Inside rearview mirror LED. |  
  
 | 
|     •  | Fog Lamp Switch Illumination is Inoperative. |  
  
|     •  | Lamp Inoperative-One Instrument Panel (Illumination Always On). |  
  
|     •  | Lamp Inoperative-One Instrument Panel (HVAC Illumination Inop). |  
  
|     •  | Lamp Inoperative-One Instrument Panel (TCS Illumination Inop). |  
  
 | 
3 
 | 
- Turn the I/P dimmer switch slowly to the LOW position.
 
- Return the I/P dimmer switch to the HIGH position.
 
 
 | 
- The brightness of the I/P, radio, HVAC and door lamps slowly decrease.
 
- The brightness of the I/P, radio, HVAC and door lamps slowly increase.
 
 
 | Lamps Erratic with
Dimmer Switch-Incandescent. 
 | 
4 
 | Turn the headlamp switch to the OFF position. 
 | The I/P lamps, HVAC, and radio illumination
lamps turn OFF. 
 | 
|     •  | Lamps Inoperative-One Instrument Panel (HVAC Illumination Always
ON). |  
  
|     •  | Lamps Inoperative-One Instrument Panel (Illumination Always On). |  
  
 | 
* Refer to the appropriate symptom diagnostic table for the applicable
abnormal result. 
 |