Step  | Action  | Value(s)  | Yes  | No  | 
|---|---|---|---|---|
1  | Did you perform the transfer case Diagnostic System Check?  | --  | Go to Diagnostic System Check  | |
2  | Verify the fault is present. Does the system operate normally?  | --  | ||
3  | Does the front axle disengage when the four wheel drive (4WD) control lever is in the two wheel drive (2WD) position?  | --  | ||
4  | Using the scan tool, under special test in instrument cluster, active the 4WD indicator lamp to OFF. Does the lamp go out?  | --  | Go to Diagnostic System Check - Instrument Cluster in Instrument Panel, Gauges and Console  | |
5  | 
 Does the scan tool show switch status no?  | --  | ||
6  | 
 Does the scan tool show switch status No?  | --  | ||
7  | 
 Does the voltage measure near the specified value?  | --  | ||
8  | Repair the short to voltage in the 4WD front wheel lock telltale feed circuit . Refer to Wiring Repairs in Wiring Systems. Did you complete the repair?  | --  | --  | |
9  | Replace the front axle actuator/switch. Refer to Electric Motor Actuator Replacement in Front Drive Axle. Did you complete the replacement?  | --  | --  | |
10  | Replace the VCM/PCM. Refer to VCM Replacement/Programming for 4.3L or Powertrain Control Module Replacement for all other engines in Engine Controls. Did you complete the replacement?  | --  | --  | |
11  | Operate the system in order to verify the repair. Did you correct the condition?  | --  | System OK  | --  |