Pinpoint Test K: the Vehicle Binds In Turns/Resists Turning/Pulsates/Shudders In A Straight Line
Four Wheel Drive (4WD) Systems - 1-Speed Torque-On-Demand
Pinpoint Tests
Pinpoint Test K: The Vehicle Binds in Turns/Resists Turning/Pulsates/Shudders in a Straight Line
Normal Operation
When the vehicle is operating in Four-Wheel Drive (4WD) AUTO mode, all 4 wheels receive the same amount of torque and rotate at the same speed. The amount of traction the vehicle can achieve depends on the amount of traction each tire can establish with the road surface. In order for the 4WD system to operate correctly, each wheel/tire assembly must have matching sizes and the front and rear axle ratios must match.
This pinpoint test is intended to diagnose the following:
- Unmatched tire sizes
- Unequal amounts of tire wear
- Unequal tire inflation pressures
- Unmatched front and rear axle ratios
PINPOINT TEST K: THE VEHICLE BINDS IN TURNS/RESISTS TURNING/PULSATES/SHUDDERS IN A STRAIGHT LINE
NOTE: 4X4 is not intended for driving on hard/dry surfaces; using 4X4 mode while driving on these surfaces may produce noises like intermittent clunking, but will not damage driveline components.
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K1 VERIFY THE CONCERN
- Test drive the vehicle on a straight stretch of road in 4X4 AUTO mode.
- Drive the vehicle through turns and parking lot maneuvers.
- Does the vehicle bind, pulsate or shudder?
Yes
If the problem occurs in 4X4 AUTO mode, GO to K2; in 4X4 mode, binding is a normal condition.
No
Go To Pinpoint Test G. Pinpoint Test G: Straightline Driveline Wind-Up
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K2 CHECK THE 4X4 MODE INDICATOR
- Review the test drive notes.
- Did the 4X4 mode indicator or the powertrain malfunction indicator illuminate?
Yes
If the powertrain malfunction indicator is illuminated, GO to K4. If the 4X4 mode indicator stays illuminated, GO to K3.
No
GO to K5.
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K3 VERIFY THE FAULT
- Review the test drive notes.
- Was 4X4 mode selected when the indicators were illuminated in the Instrument Cluster (IC) message center?
Yes
The system is functioning correctly.
No
The fault may have been caused by an intermittent, uncommanded or autolock shift. TEST the system for normal operation. Go To Pinpoint Test G. Pinpoint Test G: Straightline Driveline Wind-Up
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K4 CHECK FOR DTCs
- Connect the scan tool.
- Carry out the on-demand self-test.
- Are DTCs retrieved?
Yes
REFER to the 4X4 Control Module DTC Chart for diagnosis. Four Wheel Drive (4WD) Systems -1- Speed Torque-on-Demand
No
GO to K5.
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K5 VERIFY THE CONCERN
- Disconnect: Transfer Case C350.
- Test drive the vehicle on a straight stretch of road and in turns, and shift the transfer case through each mode. Record any fault conditions.
- Is the concern present?
Yes
INSPECT the driveline components for damage or wear. REFER to Inspection and Verification. TEST the system for normal operation. Four Wheel Drive (4WD) Systems - 1- Speed Torque-on-Demand
No
GO to K6.
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K6 CHECK THE 4WD CLUTCH PWM STATUS (4WDCPWMST) PID
- Ignition OFF.
- Connect: Transfer Case C350.
- Ignition ON.
- Clear the DTCs.
- Select 4X4 mode.
- Enter the following diagnostic mode on the scan tool: DataLogger - 4X4 Control Module.
- Monitor the 4WDCPWMST PID at closed throttle, Key ON Engine OFF (KOEO).
- Is the 4WDCPWMST PID at least 12%?
Yes
GO to K7.
No
CHECK the transfer case. TEST the system for normal operation.
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K7 CHECK THE ABS MODULE WHEEL SPEED SENSOR PIDs
- Enter the following diagnostic mode on the scan tool: DataLogger - ABS Module.
- While driving the vehicle at 30 km/h (18 mph), monitor the following wheel speed sensor PIDs:
- Left Front Wheel Speed Sensor (LF_WSPD)
- Left Rear Wheel Speed Sensor (LR_WSPD)
- Right Front Wheel Speed Sensor (RF_WSPD)
- Right Rear Wheel Speed Sensor (RR_WSPD)
- Compare the speedometer reading to the wheel speed sensor PIDs.
- Do the wheel speed sensor PIDs and speedometer speeds match within 1.5 km/h (1 mph)?
Yes
GO to K8.
No
VERIFY that the 4 road wheels are the same size and have similar tread depth. CHECK the ABS for faults. TEST the system for normal operation.
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K8 CHECK THE THROTTLE POSITION STATUS (TPI) PID
- Enter the following diagnostic mode on the scan tool: DataLogger - 4X4 Control Module.
- NOTE: The TPI PID is Accelerator Pedal Position (APP) as communicated by the PCM via High Speed Controller Area Network (HS-CAN).
- Slowly move throttle from closed throttle to Wide Open Throttle (WOT) and observe the TPI PID.
- Does the TPI PID value vary between 0 at closed throttle and 255 at WOT?
Yes
GO to K9.
No
CHECK the throttle position sensor and/or PCM for faults. REFER to Computers and Control Systems Information. TEST the system for normal operation.
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K9 CHECK THE TRANSFER CASE FRONT DRIVESHAFT OUTPUT
- With the vehicle in NEUTRAL, position it on a hoist. Refer to Maintenance/Service and Repair.
- Rotate the front driveshaft by hand.
- Does the front driveshaft rotate freely (does it require less than 45 Nm [33 lb-ft] to rotate)?
Yes
INSTALL a new 4X4 control module. REFER to 4X4 Control Module. Service and Repair TEST the system for normal operation.
No
CHECK the transfer case. TEST the system for normal operation.
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