Pinpoint Test X: The Vehicle Does Not Shift Between 2H (2WD) and 4X4 Modes Correctly
Four Wheel Drive (4WD) Systems - 2-Speed Torque-On-Demand
Pinpoint Test X: The Vehicle Does Not Shift Between 2H (2WD) and 4X4 Modes Correctly
Refer to Wiring Diagram Set 34, Four-Wheel Drive Systems for schematic and connector information Electrical Diagrams.
Normal Operation
The Mode Select Switch (MSS) communicates the operator's choice to the Transfer Case Control Module (TCCM). The TCCM (Transfer Case Control Module) then controls the transfer case synchronization clutch, transfer case motor and Integrated Wheel Ends (IWEs) as necessary. If the vehicle is not responding as intended, systematically check the necessary inputs and outputs of the TCCM (Transfer Case Control Module), components of the transfer case, IWE (Integrated Wheel End) components and halfshafts. Check all circuits for opens and shorts to power or ground.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- MSS (Mode Select Switch)
- Transfer case
- IWEs (Integrated Wheel Ends)
- IWE (Integrated Wheel End) solenoid
- TCCM (Transfer Case Control Module)
- Front axle assembly
PINPOINT TEST X : THE VEHICLE DOES NOT SHIFT BETWEEN 2H (2WD) AND 4X4 MODES CORRECTLY
WARNING: When directed to drive the vehicle as part of this test, drive the vehicle on a hard surface in an area without traffic to prevent a crash. Failure to follow these instructions may result in personal injury.
X1 CHECK FOR TCCM (Transfer Case Control Module) DTCs
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self-Test- TCCM (Transfer Case Control Module).
Are any DTCs present?
Yes
For DTC P1812:00, GO to X5.
For DTC P1815:00, GO to X7.
For DTC P1839:00, GO to X25.
For DTC P1840:00, GO to X26.
For DTC P1841:00, GO to X27.
For DTC P1849:00, GO to X21.
For DTC P1853:00, GO to X21.
For DTC P1857:00, GO to X21.
For DTC P1861:00, GO to X21.
For DTC P1867:00, GO to X4.
For DTC P1891:00, GO to X19.
For all other DTCs, REFER to the Transfer Case Control Module (TCCM) DTC Chart. Four Wheel Drive (4WD) Systems - 2-Speed Torque-on-Demand
No
GO to X2.
X2 CHECK THE TCCM (Transfer Case Control Module) IGNITION POSITION (KEY_POS_4X4) AND IGNITION STATUS (KEY_STATUS_4X4) PIDs
- Enter the following diagnostic mode on the scan tool: DataLogger- TCCM (Transfer Case Control Module).
- Monitor the KEY_POS_4X4 and KEY_STATUS_4X4 PIDs while cycling through each position.
Do the ignition PIDs match the ignition switch positions?
Yes
GO to X3.
No
If the KEY_STATUS_4X4 PID did not match, CHECK SJB (Smart Junction Box) fuse 35 (10A). If the fuse is OK, REPAIR circuit CBP35 (YE/GY). If the fuse is not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short Electrical Diagrams. TEST the system for normal operation.
If the KEY_POS_4X4 PID did not match, REFER to Steering Column to diagnose the ignition switch concern. TEST the system for normal operation.
X3 CHECK THE TCCM (Transfer Case Control Module) MODULE SUPPLY VOLTAGE (VBAT_4X4) PID
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger- TCCM (Transfer Case Control Module).
- Start the engine and monitor the VBAT_4X4 PID.
Is the VBAT_4X4 PID greater than 12 volts?
Yes
GO to X4.
No
REFER to Charging System to DIAGNOSE the low battery voltage and/or charging system concern. CLEAR the DTCs. TEST the system for normal operation.
X4 CHECK THE MSS (Mode Select Switch) POSITION MONITORING THE TCCM (Transfer Case Control Module) 4WD (Four-Wheel Drive) SWITCH STATUS (4X4_SW) PID
- Enter the following diagnostic mode on the scan tool: DataLogger- TCCM (Transfer Case Control Module).
- Monitor the 4X4_SW PID while switching to each MSS (Mode Select Switch) position.
MSS (Mode Select Switch) Position PID Status 2H 2WD 4A Automatic 4H 4WD-HIGH 4L 4WD-LOW
Does the PID always agree with the MSS (Mode Select Switch) position?
Yes
GO to X11.
No
GO to X5.
X5 CHECK THE MSS (Mode Select Switch) RESISTANCE VALUES
- Ignition OFF.
- Disconnect: MSS (Mode Select Switch) C284.
- Measure the resistance between MSS (Mode Select Switch) C284 pins 2 and 3, component side, while rotating the MSS (Mode Select Switch) through all positions. Refer to the following chart.
MSS (Mode Select Switch) Position Resistance (±1%) 2H 619 ohms 4A 270 ohms 4H 130 ohms 4L 62 ohms
Are the resistance values within specification?
Yes
GO to X6.
No
INSTALL a new MSS (Mode Select Switch). CLEAR the DTCs. TEST the system for normal operation.
X6 CHECK THE MSS (Mode Select Switch) CONTROL AND RETURN CIRCUITS FOR SHORT TO VOLTAGE
- Disconnect: TCCM (Transfer Case Control Module) C2371A.
- Ignition ON.
- Measure the voltage between MSS (Mode Select Switch) C284-3, circuit RCF13 (WH/BN), harness side and ground; and between MSS (Mode Select Switch) C284-2, circuit CCF13 (WH/BU), harness side and ground.
Is any voltage present?
Yes
REPAIR the affected circuit(s). CLEAR the DTCs. TEST the system for normal operation.
No
GO to X7.
X7 CHECK THE MSS (Mode Select Switch) CONTROL AND RETURN CIRCUITS FOR SHORT TO GROUND
- Ignition OFF.
- Disconnect: TCCM (Transfer Case Control Module) C2371A.
- Disconnect: MSS (Mode Select Switch) C284.
- Measure the resistance between MSS (Mode Select Switch) C284-3, circuit RCF13 (WH/BN), harness side and ground; and between MSS (Mode Select Switch) C284-2, circuit CCF13 (WH/BU), harness side and ground.
Are the resistances greater than 10,000 ohms?
Yes
GO to X8.
No
REPAIR the affected circuit(s). CLEAR the DTCs. TEST the system for normal operation.
X8 CHECK THE MSS (Mode Select Switch) CONTROL AND RETURN CIRCUITS FOR AN OPEN
- Measure the resistance between MSS (Mode Select Switch) C284, and TCCM (Transfer Case Control Module) C2371A, harness side. Refer to the following chart.
MSS (Mode Select Switch) Circuit TCCM (Transfer Case Control Module) C284-3 RCF13 (WH/BN) C2371A-14 C284-2 CCF13 (WH/BU) C2371A-16
Are the resistances less than 3 ohms?
Yes
GO to X9.
No
REPAIR the affected circuit(s). CLEAR the DTCs. TEST the system for normal operation.
X9 CHECK THE MSS (Mode Select Switch) CONTROL AND RETURN CIRCUITS FOR A SHORT TOGETHER
- Ignition OFF.
- Disconnect: MSS (Mode Select Switch) C284.
- Disconnect: TCCM (Transfer Case Control Module) C2371A.
- Measure the resistance between MSS (Mode Select Switch) C284-3, circuit RCF13 (WH/BN), harness side and MSS (Mode Select Switch) C284-2, circuit CCF13 (WH/BU), harness side.
Is the resistance greater than 10,000 ohms?
Yes
GO to X10.
No
REPAIR the affected circuit(s). CLEAR the DTCs.
X10 CHECK THE AVERAGE FRONT WHEEL SPEED (FRT_WHL_SPD) AND AVERAGE REAR WHEEL SPEED (REAR_WHL_SPD) PIDs
- Ignition OFF.
- Connect: TCCM (Transfer Case Control Module) C2371A.
- Connect: MSS (Mode Select Switch) C284.
- Ignition ON.
- Switch the MSS (Mode Select Switch) to 2H.
- Enter the following diagnostic mode on the scan tool: DataLogger- TCCM (Transfer Case Control Module).
- Monitor the FRT_WHL_SPD and REAR_WHL_SPD PIDs with the vehicle stopped and while driving.
Do the FRT_WHL_SPD and REAR_WHL_SPD PIDs match with the vehicle stopped and at all speeds?
Yes
GO to X11.
No
REFER to Antilock Brakes / Traction Control Systems to diagnose the wheel speed concern. After the repair is complete, CLEAR the DTCs. TEST the system for normal operation.
X11 CHECK 4WD (Four-Wheel Drive) MODES (4WD_MODES) WITH THE MSS (Mode Select Switch) IN 4H
- Start the engine.
- Switch the MSS (Mode Select Switch) to 4H.
- Monitor the 4WD_MODES PID.
Does the 4WD_MODES PID indicate 4WD (Four-Wheel Drive) High?
Yes
GO to X14.
No
GO to X12.
X12 CHECK FOR 4H WIND-UP
- Switch the MSS (Mode Select Switch) to 4H.
- Drive the vehicle on a dry, hard surface in turns.
Is wind-up present in turns?
Yes
GO to X15.
No
GO to X13.
X13 CHECK FOR TRANSFER CASE ENGAGEMENT
- With the vehicle in NEUTRAL, position it on a hoist.
- Rotate the rear driveshaft.
- Observe the front driveshaft.
Did the front driveshaft rotate?
Yes
GO to X14.
No
GO to X18.
X14 CHECK FOR IWE (Integrated Wheel End) ENGAGEMENT
- With the vehicle in NEUTRAL, position it on a hoist.
- NOTE: The engine must be idling during the following steps to supply the vacuum required for the IWEs (Integrated Wheel Ends) to engage and disengage.
Start the engine.
- Rotate the LH front tire one revolution forward and one revolution backward while observing the LH front halfshaft and U-joint.
- Rotate the RH front tire one revolution forward and one revolution backward while observing the RH front halfshaft and U-joint.
Did both front halfshafts rotate?
Yes
CHECK that all driveline fasteners are present and tightened to specification for further diagnosis of the front axle.
No
GO to Pinpoint Test N. Pinpoint Test N: The Front Axle Does Not Engage/Disengage Correctly
X15 CHECK THE TRANSFER CASE SHIFT TO 2H
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger- TCCM (Transfer Case Control Module).
- Command the Transfer Case Shift Motor Position Sense Contact Plate Power (PLATE_PWR_OS) PID to energize the transfer case gearmotor encoder assembly.
- Monitor the Transfer Case Contact Plate Switch A (PLATE_A), B (PLATE_B), C (PLATE_C) and D (PLATE_D) PIDs for the contact plate position with the MSS (Mode Select Switch) in the 2H position.
MSS (Mode Select Switch) Position Contact Plate Position PLATE_A PLATE_B PLATE_C PLATE_D 2H/4A/4H Mode CLOSED OPEN CLOSED CLOSED 4L Mode OPEN CLOSED OPEN CLOSED
Do the PIDs and message center indicate that vehicle shifted into 2H (4X2 displayed in message center for approximately 4 seconds)?
Yes
GO to X16.
No
GO to X19.
X16 CHECK FOR IWE (Integrated Wheel End) DISENGAGEMENT
- With the vehicle in NEUTRAL, position it on a hoist.
- Rotate the LH front tire one revolution forward and one revolution backward while observing the LH front halfshaft and U-joint.
- Rotate the RH front tire one revolution forward and one revolution backward while observing the RH front halfshaft and U-joint.
Did either of the front halfshafts rotate?
Yes
GO to Pinpoint Test N. Pinpoint Test N: The Front Axle Does Not Engage/Disengage Correctly
No
GO to X17.
X17 CHECK FOR TRANSFER CASE DISENGAGEMENT
- Rotate the rear driveshaft while observing the front driveshaft.
Does the front driveshaft rotate?
Yes
The system is functioning correctly. CARRY OUT the Four-Wheel Drive (4WD) Functional Test. GO to Pinpoint Test U. Pinpoint Test U: Four-Wheel Drive (4WD) System Functional Test
No
GO to X18.
X18 CHECK THE TRANSFER CASE CONTACT PLATE POSITION PIDs
- Enter the following diagnostic mode on the scan tool: DataLogger- TCCM (Transfer Case Control Module).
- Command the Transfer Case Shift Motor Position Sense Contact Plate Power (PLATE_PWR_OS) PID to energize the transfer case gearmotor encoder assembly.
- Monitor the Transfer Case Contact Plate Switch A (PLATE_A), B (PLATE_B), C (PLATE C) and D (PLATE_D) PIDs for the contact plate position with the MSS (Mode Select Switch) in the 4H position.
MSS (Mode Select Switch) Position Contact Plate Position PLATE_A PLATE_B PLATE_C PLATE_D 2H/4A/4H Mode CLOSED OPEN CLOSED CLOSED 4L Mode OPEN CLOSED OPEN CLOSED
Did the PIDs and message center indicate that the vehicle shifted into 4H (4X4 HIGH)?
Yes
GO to X29.
No
GO to X19.
X19 CHECK THE TRANSFER CASE SHIFT MOTOR OPERATION
- Remove the transfer case shift motor from the transfer case, leaving the wiring connector connected.
- Observe the transfer case shift motor while switching the MSS (Mode Select Switch) from 2H to 4H.
Does the transfer case shift motor rotate from the 2H position to the 4H position?
Yes
GO to X29.
No
GO to X20.
X20 CHECK TRANSFER PLATE CONTACT PLATE CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure the voltage between the following circuits at TCCM (Transfer Case Control Module) C2371A, harness side and ground:
Circuit C2371A Pin CCF14 (WH) 1 CCF15 (BN/YE) 2 CCF16 (VT/GN) 3 CCF17 (WH/OG) 4 RCF09 (BN/WH) 5
Is any voltage present?
Yes
REPAIR the affected circuit(s). CLEAR the DTCs. TEST the system for normal operation.
No
GO to X21.
X21 CHECK TRANSFER PLATE CONTACT PLATE CIRCUITS FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: Transfer Case C350 (if not previously disconnected).
- Disconnect: TCCM (Transfer Case Control Module) C2371A (if not previously disconnected).
- Measure the resistance between the following circuits at TCCM (Transfer Case Control Module) C2371A, harness side and ground:
Circuit C2371A Pin CCF14 (WH) 1 CCF15 (BN/YE) 2 CCF16 (VT/GN) 3 CCF17 (WH/OG) 4 RCF09 (BN/WH) 5
Are the resistances greater than 10,000 ohms?
Yes
GO to X22.
No
REPAIR the affected circuit(s). CLEAR the DTCs. TEST the system for normal operation.
X22 CHECK THE TRANSFER PLATE CONTACT PLATE CIRCUITS FOR AN OPEN
- Ignition OFF.
- Disconnect: Transfer Case C350.
- Disconnect: TCCM (Transfer Case Control Module) C2371A.
- Measure the resistance of the following circuits between TCCM (Transfer Case Control Module) C2371A, harness side and transfer case C350, harness side:
Circuit C2371A Pin C350 Pin CCF14 (GN/OG) 1 5 CCF15 (BN/YE) 2 1 CCF16 (VT/GN) 3 9 CCF17 (WH/OG) 4 13 RCF09 (BN/WH) 5 10
Are the resistances less than 3 ohms?
Yes
GO to X23.
No
REPAIR the affected circuit(s). CLEAR the DTCs. TEST the system for normal operation.
X23 CHECK THE SHIFT MOTOR FOR AN INTERNAL SHORT TO GROUND
- Measure the resistance between transfer case C350 pins 1, 5, 9, 10 and 13, component side and ground.
Are the resistances greater than 10,000 ohms?
Yes
GO to X24.
No
INSTALL a new transfer case shift motor. CLEAR the DTCs. REPEAT the self-test. If the concern is still present, GO to X30.
X24 CHECK THE SHIFT MOTOR CIRCUITS FOR POWER WHILE COMMANDING THE CW RELAY (CW_SMD_OS) AND CCW RELAY (CCW_SMD_OS) PIDs ON
- Connect: TCCM (Transfer Case Control Module) C2371A.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger- TCCM (Transfer Case Control Module).
- Command the CW_SMD_OS PID ON and OFF while measuring the voltage between transfer case C350-14, circuit CCF08 (GY/OG), harness side and ground. Then command the CCW_SMD_OS PID ON and OFF while measuring the voltage between transfer case C350-15, circuit CCF07 (BN/GN), harness side and ground.
Are the voltages 9 volts or greater on the circuits when commanding the PIDs ON?
Yes
GO to X29.
No
GO to X25.
X25 CHECK THE TCCM (Transfer Case Control Module) VOLTAGE CIRCUIT
- Ignition OFF.
- Disconnect: TCCM (Transfer Case Control Module) C2371B.
- Measure the voltage between TCCM (Transfer Case Control Module) C2371B-6, circuit SBB20 (GN/RD), harness side and ground.
Is the voltage greater than 11 volts?
Yes
GO to X26.
No
VERIFY BJB (Battery Junction Box) fuse 20 (20A) is OK. If OK, REPAIR circuit SBB20 (BN/RD). If not OK, REFER to the Wiring Diagrams to identify possible causes of the circuit short Electrical Diagrams. CLEAR the DTCs. TEST the system for normal operation.
X26 CHECK THE TRANSFER CASE SHIFT MOTOR CIRCUITS FOR AN OPEN
- Ignition OFF.
- Disconnect: TCCM (Transfer Case Control Module) C2371B.
- Disconnect: Transfer Case C350.
- Measure the resistance between transfer case C350, harness side and TCCM (Transfer Case Control Module) C2371B, harness side. Refer to the following chart.
Transfer Case Circuit TCCM (Transfer Case Control Module) C350-14 CCF08 (GY/OG) C2371B-5 C350-15 CCF07 (BN/GN) C2371B-4
Are the resistances less than 3 ohms?
Yes
GO to X27.
No
REPAIR the affected circuit(s). CLEAR the DTCs. TEST the system for normal operation.
X27 CHECK THE TRANSFER CASE SHIFT MOTOR CIRCUITS FOR SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: TCCM (Transfer Case Control Module) C2371B (if not previously disconnected).
- Disconnect: Transfer Case C350 (if not previously disconnected).
- Measure the voltage between transfer case C350-14, circuit CCF08 (GY/OG), harness side and ground; and between transfer case C350-15, circuit CCF07 (BN/GN), harness side and ground.
Is any voltage present?
Yes
REPAIR the affected circuit(s). CLEAR the DTCs. TEST the system for normal operation.
No
GO to X28.
X28 CHECK THE TRANSFER CASE SHIFT MOTOR CIRCUITS FOR SHORT TO GROUND
- Ignition OFF.
- Disconnect: TCCM (Transfer Case Control Module) C2371B (if not previously disconnected).
- Disconnect: Transfer Case C350 (if not previously disconnected).
- Measure the resistance between transfer case C350-14, circuit CCF08 (GY/OG), harness side and ground; and between the transfer case C350-15, circuit CCF07 (BN/GN), harness side and ground.
Are the resistances greater than 10,000 ohms?
Yes
GO to X29.
No
REPAIR the affected circuit(s). CLEAR the DTCs. TEST the system for normal operation.
X29 CHECK FOR CORRECT TCCM (Transfer Case Control Module) OPERATION
- Ignition OFF.
- Disconnect all TCCM (Transfer Case Control Module) connectors.
- Check for:
- corrosion.
- damaged pins
- pushed-out pins.
- Connect all TCCM (Transfer Case Control Module) connectors and make sure they are seated correctly.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes
INSTALL a new TCCM (Transfer Case Control Module). REFER to 4X4 Control Module . TEST the system for normal operation.
No
The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. ADDRESS the root cause of the connector concern. TEST the system for normal operation.
X30 SHIFT THE TRANSFER CASE TO 4H MANUALLY
- Remove the transfer case shift motor from the transfer case.
- Using a suitable wrench, rotate the shift cam to the 4H position.
- Rotate the rear driveshaft and watch the front driveshaft.
Does the transfer case shift to 4H and the front driveshaft rotates?
Yes
GO to X31.
No
REPAIR the transfer case.
X31 CHECK THE TORQUE REQUIRED TO SHIFT THE TRANSFER CASE
- Rotate the shift cam by hand through 4L, 4H and 2H positions.
- Measure the torque required to perform the shift.
Is the torque required to shift 45 Nm (33 lb-ft) or less?
Yes
GO to X32.
No
REPAIR the transfer case.
X32 SHIFT THE TRANSFER CASE TO 2H MANUALLY
- Rotate the shift cam to the 2H position.
- Rotate the rear driveshaft and watch the front driveshaft.
Does the transfer case shift to 2H and the front driveshaft does not rotate?
Yes
GO to X33.
No
REPAIR the transfer case.
X33 SHIFT THE TRANSFER CASE TO 4L MANUALLY
- Rotate the shift cam by hand to the 4L position.
- Rotate the rear driveshaft and watch the front driveshaft.
Does the transfer case shift to 4L and the front driveshaft rotates?
Yes
INSTALL a new transfer case shift motor. REFER to Transfer Case Shift Motor . CLEAR the DTCs. TEST the system for normal operation.
No
REPAIR the transfer case.