Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Transfer Case Diagnostic System Test? | -- | Go to Step 2 | Go to Diagnostic System Check in Transfer Case |
2 | Inspect the 4WD indicator lamp. Refer to Switch Indicator Lamps Do Not Light - One or More in Transfer Case. Does the 4WD indicator lamp light? | -- | System OK | Go to Step 3 |
3 | Check the electrical system of the front drive axle. Refer to Front Axle Will Not Engage in Transfer Case. Does the 4WD engage? | -- | System OK | Go to Step 4 |
4 | Inspect the vacuum hoses. Are the vacuum hoses kinked, disconnected, damaged or plugged? | -- | Go to Step 5 | Go to Step 6 |
5 | Replace the vacuum hoses. Does the 4WD engage? | -- | System OK | Go to Step 6 |
6 | Inspect for engine vacuum at the vacuum actuator. Is there vacuum at the actuator? | -- | Go to Step 8 | Go to Step 7 |
7 | Replace the vacuum actuator. Refer to Vacuum Actuator Replacement . Does the 4WD engage? | -- | System OK | Go to Step 8 |
8 | Inspect the cable. Is the cable damaged, disconnected or binding? | -- | Go to Step 9 | Go to Step 10 |
9 | Replace the cable. Refer to Shift Cable Replacement . Does the 4WD engage? | -- | System OK | Go to Step 10 |
10 | inspect the operation of the shift fork. Use J 33798 . Refer to J 33798 - Hub Engagement Tool . Does the 4WD engage? | -- | System OK | Go to Step 11 |
11 | Replace the shift fork. Refer to Shift Fork Replacement . Does the 4WD engage? | -- | System OK | Go to Step 12 |
12 | The cause of concern may be in the front drive axle. Disassemble the front drive axle. Inspect for damaged components. Refer to Differential Carrier Assembly Disassemble . Does the 4WD engage? | -- | System OK | Go to Step 1 |
