Pinpoint Test C: The Vehicle Does Not Shift Between 2-Wheel Drive (2WD) and Four-Wheel Drive (4WD) Modes Correctly
Four Wheel Drive (4WD) Systems - Electronic Shift
Pinpoint Tests
Pinpoint Test C: The Vehicle Does Not Shift Between 2-Wheel Drive (2WD) and Four-Wheel Drive (4WD) Modes Correctly
Refer to Wiring Diagram Set 34, Four-Wheel Drive System for schematic and connector information. Diagrams By Number
Normal Operation
The Mode Select Switch (MSS) communicates the operator's choice to the 4X4 control module. The 4X4 control module then controls the transfer case clutch and transfer case shift motor as necessary. If the vehicle is not responding to the operator's intentions, systematically check the necessary inputs and outputs of the 4X4 control module, components of the transfer case and halfshafts. Check all circuits for opens and shorts to power or ground.
This pinpoint test is intended to diagnose the following:
- Transfer case
- 4X4 control module
- Front axle assembly
- MSS
- Wiring, terminals or connectors
PINPOINT TEST C: THE VEHICLE DOES NOT SHIFT BETWEEN 2-WHEEL DRIVE (2WD) AND FOUR-WHEEL DRIVE (4WD) MODES CORRECTLY
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C1 CHECK FOR DTCs
- Connect the scan tool.
- Carry out the 4X4 control module on-demand self test.
- Are DTCs retrieved?
Yes
If DTC P1812, GO to C8. If DTC P1815, GO to C11. DTC P1867 or P1891, GO to C19. If DTC P1849, P1853, P1857 or P1861, GO to C21.
No
GO to C2.
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C2 CHECK FOR VOLTAGE INPUT TO THE 4X4 CONTROL MODULE
- Disconnect: 4X4 Control Module C281b.
- Measure the voltage between C281b-6, circuit SBB27 (BU/RD) and ground.
- Is the voltage greater than 9 volts?
Yes
GO to C6.
No
GO to C3.
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C3 CHECK THE HOT AT ALL TIMES-2 BJB FUSE 27 (20A)
- Check Battery Junction Box (BJB) fuse 27 (20A).
- Is the fuse OK?
Yes
GO to C4.
No
CHECK circuit SBB27 (BU/RD) for a short to ground or open. REPAIR as necessary. REPEAT the self-test.
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C4 CHECK FOR BATTERY VOLTAGE FROM THE BJB
- Ignition ON.
- Measure the voltage between BJB input side fuse cavity 27 and ground.
- Is the voltage greater than 9 volts?
Yes
REPAIR or INSTALL new components as necessary. REPEAT the self-test.
No
GO to C5.
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C5 CHECK THE BATTERY VOLTAGE WITH THE ENGINE RUNNING
- Start the engine.
- Measure the battery voltage at the positive battery terminal.
- Is the voltage greater than 9 volts?
Yes
REPAIR circuit SBB27 (BU/RD) at the Battery Junction Box (BJB). REPEAT the self-test.
No
CHECK the charging system. REFER to Charging System Testing and Inspection.
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C6 CHECK GROUND TO 4X4 CONTROL MODULE FOR AN OPEN
- Disconnect the battery ground cable. Refer to Battery, Mounting and Cables Battery Disconnect.
- Disconnect: 4X4 Control Module C281b.
- Measure the resistance between 4X4 control module C281b-10 circuit GD161 (BK/YE), harness side and harness ground point.
Refer to Wiring Diagram Set 10, Grounds for schematic and connector information. Diagrams By Number
- Is the resistance less than 5 ohms?
Yes
Disconnect all 4X4 control module connectors. CHECK for corrosion and/or pushed-out pins. The condition may have been caused by a loose or corroded connector. REPAIR or CLEAN as necessary.GO to C7.
If not, INSTALL a new 4X4 control module. REFER to 4X4 Control Module Service and Repair. REPEAT the self-test.
No
REPAIR the affected circuit(s). REPEAT the self-test.
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C7 CHECK THE IGNITION SWITCH STATUS PID
- Connect the battery ground cable. Refer to Battery, Mounting and Cables Battery Disconnect.
- Ignition ON.
- Monitor the following ignition switch PIDs:
- Ignition Switch - Off/Unlock Position (IGN_O/U)
- ACC Position (IGN_A)
- Start Position 3 (IGN_S)
- Ignition Switch - Run/Start Position (IGN_R/S)
- Ignition Switch - Run Position (IGN_R)
- Do the ignition switch PIDs match the ignition switch positions?
Yes
GO to C8.
No
If the IGN_R/S PID did not match, CHECK SJB fuse 10 (10A). If the fuse is OK, REPAIR circuit CBP10 (YE/OG). CLEAR the DTCs. REPEAT the self-test.
If the IGN_O/U, IGN_A, IGN_S or IGN_R PIDs did not match, REFER to Steering Column Switches Testing and Inspection to diagnose the ignition switch concern.
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C8 CHECK THE 4WD SWITCH STATUS (4WD_SW) POSITION PIDs
- Ignition OFF.
- Connect the scan tool.
- Ignition ON.
- Monitor the 4WD_SW PID while cycling through each MSS position.
- Does the 4WD_SW PID always agree with the switch position?
Yes
GO to C13.
No
GO to C9.
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C9 CHECK CIRCUITS CCF13 (WH/BU) AND RCF13 (WH/BN) FOR AN OPEN
- Disconnect: 4X4 Control Module C281a.
- Disconnect: MSS C284.
- Measure the resistance between MSS C284-2, harness side and 4X4 control module C281a-11, harness side, circuit CCF13 (WH/BU).
- Measure the resistance between MSS C284-3, harness side and 4X4 control module C281a-20, harness side, circuit RCF13 (WH/BN).
- Is the resistance less than 5 ohms?
Yes
GO to C10.
No
REPAIR the affected circuit(s). CLEAR the DTCs. REPEAT the self-test.
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C10 CHECK CIRCUITS CCF13 (WH/BU) AND RCF13 (WH/BN) FOR A SHORT TO VOLTAGE
- Measure the voltage between MSS C284-2, circuit CCF13 (WH/BU) harness side and ground.
- Measure the voltage between MSS C284-3, circuit RCF13 (WH/BN) harness side and ground.
- Is any voltage present?
Yes
REPAIR the affected circuit(s). CLEAR the DTCs. REPEAT the self-test.
No
GO to C11.
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C11 CHECK CIRCUITS CCF13 (WH/BU) AND RCF13 (WH/BN) FOR A SHORT TO GROUND
- Disconnect: MSS C284.
- Measure the resistance between MSS C284-2, circuit CCF13 (WH/BU) harness side and ground.
- Measure the resistance between MSS C284-3, circuit RCF13 (WH/BN) harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to C12.
No
REPAIR the affected circuit(s). CLEAR the DTCs. REPEAT the self-test.
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C12 CHECK THE MSS
- Ignition OFF.
- Measure the resistance between MSS terminals 2 and 3 component side, while rotating the switch through all positions. Refer to the following chart.
- Are the resistance values within specification?
Yes
GO to C27.
No
INSTALL a new MSS. REFER to Mode Select Switch (MSS) Service and Repair. CLEAR the DTCs. REPEAT the self-test.
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C13 CHECK FOR 4X4 HIGH WIND-UP
- Switch the MSS to 4H.
- Drive the vehicle on a dry, hard surface in turns.
- Is wind-up present in turns?
Yes
GO to C15.
No
GO to C14.
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C14 CHECK FOR TRANSFER CASE ENGAGEMENT
- With the vehicle in NEUTRAL, position it on a hoist. Refer to Jacking and Lifting Service and Repair.
- Rotate the rear driveshaft.
- Observe the front driveshaft.
- Did the front driveshaft rotate?
Yes
CHECK that all driveline fasteners are present and tightened to specification. REFER to Driveline System - General Information Testing and Inspection for further diagnosis of the front axle.
No
GO to C17.
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C15 CHECK THE TRANSFER CASE SHIFT TO 2H
- Ignition OFF.
- Connect the scan tool.
- Ignition ON.
- Using the active command contact plate power (PLATE_PWR) to energize the transfer case motor contact plate position return circuit.
- Monitor the 4X4 control module transfer case contact plate switch A (PLATE_A), B (PLATE_B), C (PLATE_C) and D (PLATE_D) PIDs for the contact plate position while switching the MSS to 2H.
- Does the 4X4 control module PID and Instrument Cluster (IC) indicator lamp indicate that the vehicle shifted into 2WD?
Yes
GO to C16.
No
GO to C19.
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C16 CHECK FOR TRANSFER CASE DISENGAGEMENT
- With the vehicle in NEUTRAL, position it on a hoist. Refer to Jacking and Lifting Service and Repair.
- Rotate the rear driveshaft while observing the front driveshaft.
- Does the front driveshaft rotate?
Yes
The system is functioning correctly.
No
GO to C17.
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C17 CHECK THE TRANSFER CASE CONTACT PLATE POSITION PIDs
- Connect the scan tool.
- NOTE: Once the contact plate power (PLATE_PWR) active command is activated, it is necessary to re-enter DataLogger and deselect then reselect the PLATE_PWR active command when the MSS is placed in a different position.
- Using the active command contact plate power (PLATE_PWR) to energize the transfer case motor contact plate position return circuit.
- Monitor the 4X4 control module Transfer Case Contact Plate Switch A (PLATE_A), B (PLATE_B), C (PLATE_C) and D (PLATE_D) PIDs.
- Switch the MSS from 2H to 4H.
- Does the transfer case contact plate PID indicate 4H?
Yes
GO to C28.
No
GO to C18.
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C18 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 from 2H to 4H.
- Does the transfer case shift motor rotate from the 2WD position to the 4X4 HIGH position?
Yes
GO to C28.
No
GO to C19.
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C19 CHECK CIRCUITS CCF14 (GN/OG), CCF15 (BN/YE), CCF16 (VT/GN), CCF17 (WH/OG) AND RCF09 (BN/WH) FOR AN OPEN
- Ignition OFF.
- Disconnect: Transfer Case C350.
- Disconnect: 4X4 Control Module C281a.
- Measure the resistance of the following circuits between transfer case C350 harness side and 4X4 control module C281a harness side:
- Are the resistances less than 5 ohms?
Yes
GO to C20.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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C20 CHECK CIRCUITS CCF14 (GN/OG), CCF15 (BN/YE), CCF16 (VT/GN), CCF17 (WH/OG) AND RCF09 (BN/WH) FOR A SHORT TO VOLTAGE
- Measure the voltage between the following circuits at transfer case C350, harness side and ground:
- Is any voltage present?
Yes
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
No
GO to C21.
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C21 CHECK CIRCUITS CCF14 (GN/OG), CCF15 (BN/YE), CCF16 (VT/GN), CCF17 (WH/OG) AND RCF09 (BN/WH) FOR A SHORT TO GROUND
- Measure the resistance between the following circuits at transfer case C350, harness side and ground:
- Are the resistances greater than 10,000 ohms?
Yes
GO to C22.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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C22 CHECK THE SHIFT MOTOR FOR AN INTERNAL SHORT TO GROUND
- Measure the resistance between shift motor pins 1, 2, 3, 5 and 6, component side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to C23.
No
INSTALL a new transfer case shift motor. REFER to Transfer Case Shift Motor Service and Repair. CLEAR the DTCs. REPEAT the self-test. GO to C27.
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C23 CHECK CIRCUITS CCF08 (GY/OG) AND CCF07 (BN/GN) FOR POWER USING THE CLOCKWISE RELAY CONTROL (CW_RELAY) AND COUNTERCLOCKWISE RELAY CONTROL (CCW_RELAY) ACTIVE COMMANDS
- Connect: 4X4 Control Module C281A.
- Enter the following diagnostic mode on the scan tool: DataLogger - 4X4 Control Module.
- Command the CW_RELAY active command ON and OFF and measure the voltage between transfer case C350-4, circuit CCF07 (BN/GN), harness side and ground. Command the CCW_RELAY active command ON and OFF and measure the voltage between transfer case C350-7, circuit CCF08 (GY/OG), harness side and ground.
- Are the voltages 9 volts or greater on the circuit being commanded?
Yes
INSTALL a new transfer case shift motor. REFER to Transfer Case Shift Motor Service and Repair. CLEAR the DTCs. REPEAT the self-test. GO to C27.
No
GO to C24.
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C24 CHECK CIRCUITS CCF07 (BN/GN) AND CCF08 (GY/OG) FOR AN OPEN
- Ignition OFF.
- Disconnect: 4X4 Control Module C281b.
- Measure the resistance between transfer case C350-4, harness side and 4X4 control module C281b-5, harness side circuit CCF07 (BN/GN).
- Measure the resistance between transfer case C350-7, harness side and 4X4 control module C281b-4, harness side circuit CCF08 (GY/OG).
- Are the resistances less than 5 ohms?
Yes
Connect 4X4 control module C281b. GO to C25.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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C25 CHECK CIRCUITS CCF07 (BN/GN) AND CCF08 (GY/OG) FOR A SHORT TO POWER
- Ignition ON.
- Measure the voltage between transfer case C350-4, circuit CCF07 (BN/GN), harness side and ground; and between transfer case C350-7, circuit CCF08 (GY/OG), harness side and ground.
- Measure the voltage between transfer case C350-7, circuit CCF08 (GY/OG), harness side and ground.
- Is any voltage present?
Yes
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
No
GO to C26.
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C26 CHECK CIRCUITS CCF07 (BN/GN) AND CCF08 (GY/OG) FOR A SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between transfer case C350-4, circuit CCF07 (BN/GN), harness side and ground.
- Measure the resistance between transfer case C350-7, circuit CCF08 (GY/OG), harness side and ground.
- Are the resistances greater than 10,000 ohms?
Yes
GO to C27.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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C27 ATTEMPT TO DUPLICATE THE CONCERN
- Inspect and, if necessary, clean the 4X4 control module and connectors.
- Drive the vehicle and attempt to duplicate the concern.
- Is the concern still present?
Yes
INSTALL a new 4X4 control module. REFER to 4X4 Control Module Service and Repair. REPEAT the self-test.
No
CLEAR the DTCs. REPEAT the self-test.
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C28 SHIFT THE TRANSFER CASE TO 4X4 HIGH MANUALLY
- Remove the transfer case shift motor from the transfer case.
- Using a suitable wrench, rotate the shift cam to the 4X4 HIGH position.
- Rotate the rear driveshaft and watch the front driveshaft.
- Does the transfer case shift to 4X4 HIGH and the front driveshaft rotate?
Yes
GO to C29.
No
REPAIR the transfer case. REFER to Transfer Case Overhaul.
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C29 CHECK THE TORQUE REQUIRED TO SHIFT THE TRANSFER CASE
- Rotate the shift cam by hand through 4X4 LOW, N and 4X4 HIGH positions.
- Measure the torque required to carry out the shift.
- Is the torque required to shift 45 Nm (33 lb-ft) or less?
Yes
GO to C30.
No
REPAIR the transfer case. REFER to Transfer Case Overhaul.
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C30 SHIFT THE TRANSFER CASE TO 2WD MANUALLY
- Rotate the shift cam to the 2WD position.
- Rotate the rear driveshaft and watch the front driveshaft.
- Does the transfer case shift to 2WD and the front driveshaft not rotate?
Yes
GO to C31.
No
REPAIR the transfer case. REFER to Transfer Case Overhaul.
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C31 SHIFT THE TRANSFER CASE TO 4X4 LOW MANUALLY
- Rotate the shift cam by hand to the 4X4 LOW position.
- Rotate the rear driveshaft and watch the front driveshaft.
- Does the transfer case shift to 4X4 LOW and the front driveshaft rotate?
Yes
INSTALL a new transfer case shift motor. REFER to Transfer Case Shift Motor Service and Repair.
No
REPAIR the transfer case. REFER to Transfer Case Overhaul.
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