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Pinpoint Tests




Suspension System

Pinpoint Tests



Pinpoint Test A: Vehicle Drifts/Pulls

This pinpoint test is intended to diagnose the following:
- Unevenly loaded vehicle
- Tire pressure
- Tire forces
- Brake drag
- Incorrect vehicle alignment
- Steering system




PINPOINT TEST A: VEHICLE DRIFTS/PULLS

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A1 CHECK FOR UNEVENLY LOADED VEHICLE



- Visually check the vehicle for an uneven loading condition.
- Is the vehicle unevenly loaded?

Yes
ADVISE the customer of uneven loading condition.

No
GO to A2.

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A2 CHECK THE TIRE PRESSURES AND TIRE CONDITIONS



- Check the tire pressures. Refer to the Vehicle Certification (VC) label located on the driver door jamb. Check the tires for uneven/abnormal wear. Refer to Diagnosis and Testing - Wheels and Tires. Testing and Inspection
- Are the tire pressures and tire conditions OK?

Yes
GO to A3.

No
ADJUST the tire pressures to the specified pressure or INSTALL new tires as necessary.

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A3 ISOLATE TIRE DRIFT/PULL CONDITION



- Cross the front wheel and tire assemblies from left-to-right. Refer to Wheels and Tires.
- Does the vehicle drift/pull?

Yes
If the vehicle drifts/pulls in the opposite direction, tire forces are causing the drift/pull. REFER to Wheels and Tires to diagnose tire drift/pull. If the vehicle drifts/pulls in the same direction, GO to A4.

No
Tire forces were causing the drift/pull and the concern has been corrected.

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A4 CHECK FOR BRAKE DRAG



- Spin all 4 wheel and tire assemblies by hand and check for brake drag.
- Do the wheels spin freely?

Yes
GO to A5.

No
REFER to Brakes and Traction Control to diagnose brake drag condition.

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A5 CHECK THE WHEEL ALIGNMENT



- Using alignment equipment and the manufacturer's instructions, check the wheel alignment.
- Is the wheel alignment out of specification?

Yes
ADJUST the alignment as necessary. REFER to General Procedures.

No
REFER to Steering to diagnose steering system drift/pull/wander condition.

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