Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Transfer Case Control Schematics DEFINITION: 4WD always engaged, all other engine and transmission functions are normal. | |||
1 | Did you review the Transfer Case Description and Operation and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Transfer Case |
2 |
Does the 4WD system disengage? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 |
3 | Is the 4WD indicator illuminated? | Go to Step 4 | Go to Step 6 |
4 | Test the operation of the four wheel drive switch. The switch should be closed in four wheel drive and open in two wheel drive. Refer to Circuit Testing in Wiring Systems. Does the four wheel drive switch operate properly? | Go to Step 5 | Go to Step 7 |
5 | Test the four wheel drive switch signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 6 |
6 | Test the axle actuator control circuits for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 8 |
7 | Inspect for a poor connection at the harness connector of the four wheel drive 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 11 | Go to Step 9 |
8 | Inspect for a poor connection at the harness connector of the front drive axle actuator pump. 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 11 | Go to Step 10 |
9 | Replace the four wheel drive switch. Did you complete the replacement? | Go to Step 11 | -- |
10 | Replace the front drive axle actuator pump. Refer to Electric Motor Actuator Replacement in Front Axle Drive. Did you complete the replacement? | Go to Step 11 | -- |
11 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
