Operation CHARM: Car repair manuals for everyone.

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

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.

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.

A3 ISOLATE TIRE DRIFT/PULL CONDITION

- Cross the front wheel and tire assemblies from left-to-right.

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 the 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.

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.

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. For Electronic Power Assist Steering (EPAS) vehicles, refer to Steering to diagnose steering system drift/pull/wander condition. For Hydraulic Power Assist Steering (HPAS) vehicles, refer to Steering to diagnose steering system drift/pull/wander condition.