Pinpoint Test F: 4WD System Functional Test
- F1 CHECK 4WD INDICATOR PROVE-OUT
- Key in ON position.
- Do the 4WD indicators illuminate at prove out?
Yes GO to F2.
No CHECK the instrument cluster. REFER to INFORMATION, GAUGES & WARNING DEVICES .
- F2 CHECK 4WD AUTO OPERATION
- If in 4L, switch the MSS to 4WD AUTO.
- Are the 4WD indicators off?
Yes GO to F5.
No GO to F3.
- F3 CHECK FOR DTCs
- Connect the diagnostic tool.
- CARRY-OUT the on-demand self-test.
- Are DTCS present?
Yes REFER to the 4x4 Control Module (PCM) DTC Index for diagnosis.
No GO to F4.
- F4 CHECK FOR WIND-UP IN 4WD AUTO
- Drive the vehicle on a dry, hard surface in turns.
- Is wind-up present in turns?
Yes If 4L indicator is on, Go To PINPOINT TEST E . If the 4H indicator is on, Go To PINPOINT TEST B .
No Go To PINPOINT TEST C .
- F5 CHECK THE TRANSFER CASE CLUTCH DUTY CYCLE PID
- Enter the following diagnostic mode on the diagnostic tool: PID/DATA Monitor and Record.
- Monitor the transfer case clutch duty cycle (pulse width modulated-(PWM)) PID.
- Does the PID indicate 2 to 4% clutch application at closed throttle?
Yes GO to F7.
No GO to F6.
- F6 CHECK THE CONTACT PLATE ENCODER PIDs
- Enter the following diagnostic mode on the diagnostic tool: PID/DATA Monitor and Record.
- Monitor the contact plate position PIDs. Refer to the following chart:CONTACT PLATE POSITION PID REFERENCE CHART
Contact Plate Position PID MSS PID 4WD AUTO/4H MSS PID 4L PLATE_A CLOSED OPEN PLATE_B OPEN CLOSED PLATE_C CLOSED OPEN PLATE_D CLOSED CLOSED - Does the contact plate position PID indicate that the shift motor is in 4x4 Auto?
Yes Go To PINPOINT TEST B .
No Go To PINPOINT TEST E .
- F7 CHECK SHAFT SPEED PIDs
- Enter the following diagnostic mode on the diagnostic tool: PID/DATA Monitor and Record.
- Monitor the transfer case front and rear shaft speeds.
- Drive the vehicle 30 km/h (18 mph).
- Record and compare the front wheel speed and the rear wheel speed.
- Do the front shaft speed and rear shaft speed values match within 1.5 km/h (1 mph)?
Yes GO to F8.
No CHECK the ABS system. Refer to ANTI-LOCK CONTROL and VERIFY that the four road tire sizes match.
- F8 CHECK THE THROTTLE POSITION PID
- Enter the following diagnostic mode on the diagnostic tool: PID/DATA Monitor and Record.
- Monitor the throttle position PID from the 4x4 module.
- Key ON, engine OFF.
- Slowly move throttle from closed throttle to WOT and observe the 4x4 module throttle sensor PID.
- Does the PID value vary between 0% at closed throttle and 100% at WOT?
Yes GO to F9.
No CHECK the throttle position sensor and/or PCM. Refer to INTRODUCTION - CNG, FLEX-FUEL & GASOLINE .
- F9 CHECK FOR WIND-UP IN TURNS ON THROTTLE
- Drive the vehicle on a dry, hard surface, executing turns while applying the throttle.
- Is wind-up present?
Yes CHECK the transfer case. REFER TRANSFER CASE - ELECTRONIC SHIFT .
No GO to F10.
- F10 CHECK 4H OPERATION
- Select 4H.
- Does the 4H indicator illuminate correctly?
Yes GO to F11.
No GO to F12.
- F11 CHECK FOR 4H WIND-UP
- Drive the vehicle on a dry, hard surface in turns.
- Is wind-up present in turns?
Yes GO to F14.
No Go To PINPOINT TEST B .
- F12 CHECK FOR DTCs
- Connect the diagnostic tool.
- CARRY-OUT the on-demand self-test.
- Are DTCS present?
Yes REFER to the 4x4 Control Module (PCM) DTC Index for diagnosis.
No GO to F13.
- F13 CHECK FOR WIND-UP IN 4H ON THROTTLE
- Drive the vehicle on a dry, hard surface in turns while applying the throttle.
- Is wind-up present in turns?
Yes Go To PINPOINT TEST C .
No Go To PINPOINT TEST B .
- F14 CHECK 4L OPERATION
- Select 4L:
- vehicle stationary.
- press the brake.
- shift the transmission to N (neutral).
- select 4L.
- wait for the 4WD LOW indicator to illuminate in the instrument cluster indicating that the shift is complete.
- Does the 4L indicator illuminate?
Yes GO to F15.
No GO to F16.
- F15 CHECK FOR WIND-UP IN 4L MODE
- Drive the vehicle on a dry, hard surface in turns while applying the throttle.
- Is wind-up present in turns?
Yes GO to F19.
No GO to F17.
- F16 CHECK FOR DTCs
- Connect the diagnostic tool.
- CARRY-OUT the on-demand self-test.
- Are DTCS present?
Yes REFER to the 4x4 Control Module (PCM) DTC Index for diagnosis.
No GO to F18.
- F17 CHECK FOR DTCs
- Connect the diagnostic tool.
- CARRY-OUT the on-demand self-test.
- Are DTCs present?
Yes REFER to the 4x4 Control Module (PCM) DTC Index for diagnosis.
No Go To PINPOINT TEST F .
- F18 CHECK FOR WIND-UP IN 4L MODE
- Drive the vehicle on a dry, hard surface in turns while applying the throttle.
- Is wind-up present in turns?
Yes Go To PINPOINT TEST C .
No Go To PINPOINT TEST E .
- F19 CHECK 4WD AUTO OPERATION
- Switch the MSS to 4WD AUTO.
- Do the 4WD indicators turn off?
Yes The 4WD system is operating correctly.
No GO to F20.
- F20 CHECK FOR DTCs
- Carry-out the on-demand self-test.
- Are DTCs retrieved?
Yes Refer the 4x4 Control Module (PCM) DTC Index.
No GO to F21.
- F21 CHECK FOR WIND-UP IN 4WD AUTO
- Drive the vehicle on a dry, hard surface in turns.
- Is wind-up present in turns?
Yes Go To PINPOINT TEST C .
No Go To PINPOINT TEST E .