Pinpoint Test W: The Vehicle Binds In Turns/Resists Turning/Pulsates/Shudders In A STRAIGHTLINE
WARNING: This page is about a different car, the 2007 Lincoln Mark LT and 2007 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
4H mode is not intended for driving on hard/dry surfaces.
- W1 VERIFY THE CONCERN
- Test drive the vehicle on a straight stretch of road in all wheel drive (AWD) mode.
- Drive the vehicle through turns and parking lot maneuvers.
- Does the vehicle bind, pulsate or shudder?
- YES : If the problem occurs in AWD mode, go to W2 . If the problem occurs in AWD LOCKED mode, binding is a normal condition.
- NO : Go to Pinpoint Test X .
- W2 CHECK THE 4H INDICATOR
- Review the test drive notes.
- Did the 4H indicator illuminate or flash?
- W3 VERIFY THE FAULT
- Review the test drive notes.
- Was 4H selected when the 4H indicator was illuminated?
- 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 X .
- W4 CHECK FOR DTCS
- Connect the diagnostic tool.
- Carry out the on-demand self test.
- Are DTCs retrieved?
- YES : REFER to the Four Wheel Drive (4WD) Control Module Diagnostic Trouble Code (DTC) Chart for diagnosis.
- NO : Go to W5.
- W5 VERIFY THE CONCERN
- Disconnect: Transfer Case C3146
- Test drive the vehicle on a straight stretch of road, shift the transfer case through each mode. Record any fault conditions.
- Is the concern present?
- YES : Vehicles with limited slip rear differential: The condition is normal and no repair action is necessary. Vehicles without limited slip rear differential: INSPECT the driveline components for damage or wear. REFER to Inspection and Verification .
- NO : Go to W6.
- W6 CHECK THE TRANSFER CASE CLUTCH DUTY CYCLE PID
- Connect: Transfer Case C3146
- CLEAR the DTCs.
- 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 at closed throttle, engine OFF, key ON.
- Is the clutch duty cycle greater than 10%?
- YES : Go to W7.
- NO : CHECK the transfer case. REFER to TRANSFER CASE article.
- W7 CHECK SHAFT SPEED PIDs
- Enter the following diagnostic mode on the diagnostic tool: PID/DATA Monitor and Record
- While driving the vehicle at 30 km/h (18 mph), monitor the wheel speed PIDs.
- Compare the speedometer reading to the wheel speed PIDs.
- Do the wheel speed PIDs and speedometer speeds match within 1.5 km/h (1 mph)?
- YES : Go to W8.
- NO : VERIFY that the 4 road wheels are the same size and have similar tread depth, then, CHECK the ABS system for faults. REFER to VEHICLE DYNAMIC SYSTEMS article.
- W8 CHECK THE THROTTLE POSITION SENSOR PID
- Enter the following diagnostic mode on the diagnostic tool: PID/DATA Monitor and Record
- Slowly move throttle from closed throttle to WOT and observe the throttle position sensor PID.
- Does the value vary between 0% at closed throttle and 100% at WOT?
- YES : Go to W9.
- NO : CHECK the throttle position sensor and/or PCM for faults. Refer to INTRODUCTION - GASOLINE ENGINES article.
- W9 CHECK THE TRANSFER CASE FRONT DRIVESHAFT OUTPUT
- With the vehicle in NEUTRAL, position it on a hoist. Refer to JACKING AND LIFTING article.
- Rotate the front driveshaft by hand.
- Do the front driveshaft rotate freely (does it require less than 45 Nm [33 lb-ft] to rotate)?
- YES : INSTALL a new 4WD control module (PCM). REFER to ELECTRONIC ENGINE CONTROLS article. REPEAT the self-test.
- NO : CHECK the transfer case. REFER to TRANSFER CASE article. TEST the system for normal operation.