Ford Mustang (1999-2004) Service Manual: Pinpoint Tests

GO to A2 .

No

CORRECT as necessary.

RETEST for normal operation.

• Check tires for uneven and excessive wear and for correct pressure.

• Are the tires OK?

GO to A3 .

No

CORRECT alignment as necessary. RETEST for correct operation.

• Check the caster, camber and toe.

• Is the alignment OK?

GO to A4 .

No

REPAIR or INSTALL new components as necessary.

RETEST for normal operation.

• Check all disc brake calipers, anchor plate guide pins and brake pads for binding, wear, damage, contamination and correct installation.

• Are the disc brake calipers, anchor plate guide pins and brake pads OK?

REPAIR or INSTALL new front disc brake caliper or anchor plate guide pins on the side opposite to the direction of the drift or pull.

No

REPAIR or INSTALL new front disc brake caliper or anchor plate guide pins on the side of the vehicle in the direction of the drift or pull.

• Road test the vehicle, and observe whether the drift occurs with or without the brakes applied.
• Does the drift or pull occur with the brakes applied?

GO to B2 .

No

INSTALL a new brake master cylinder reservoir. TEST the system for normal operation.

• Key in OFF position.
• Disconnect: Brake Master Cylinder Fluid Level Switch C124.
• Connect a fused jumper from C124-2 circuit 977 (PK/WH) to C124-3 circuit 128 (VT/YE).

• Key in ON position.
• Does the brake warning indicator stay on?

GO to B3 .

No

INSTALL a new parking brake switch. TEST the system for normal operation.

• Key in OFF position.
• Disconnect: Parking Brake Switch.
• Key in ON position.
• Does the brake warning light stay on?

REPAIR the GEM. TEST the system for normal operation.

No

For vehicles without Daytime Running Lights (DRL), GO to B4 . For vehicles with DRL, GO to B5 .

• Key in OFF position.
• Disconnect: GEM C201e.
• Measure resistance to ground at C201e-13.

• Is the resistance greater than 10,000 ohms?

REPAIR the ground short in circuit 128 (VT/YE). TEST the system for normal operation.

No

REPAIR the ground short in circuit 977 (VT/WH) or circuit 22 (LB/BK). TEST the system for normal operation.

• Remove the fused jumper from C124.
• Measure the resistance to ground at C124-2.

• Is the resistance greater than 10,000 ohms?

GO to B6 .

No

REPAIR the ground short in circuit 128 (VT/YE). TEST the system for normal operation.

• Remove the fused jumper from C124.
• Measure the resistance to ground at C201e-13.

• Is the resistance greater than 10,000 ohms?

REPAIR the DRL module. TEST the system for normal operation.

No

REPAIR the ground short in circuit 22 (LB/BK) or 977 (VT/WH). TEST the system for normal operation.

• Disconnect: DRL Module C1030.
• Measure the resistance to ground at C124-2.

• Is the resistance greater than 10,000 ohms?

GO to C2 .

No

CORRECT as necessary. RETEST for normal operation.

• Inspect the tires for uneven or excessive wear, correct pressure, correct size and type.
• Are the tires OK?

GO to C3 .

No

CORRECT as necessary. RETEST for normal operation.

• Inspect the brake pads and brake discs for wear, damage, contamination and correct installation.
• Are the brake components OK?

INSPECT the disc brake calipers and INSTALL new calipers as necessary.

RETEST for normal operation.

No

INSTALL a new proportioning valve.

RETEST for normal operation.

• Install the gauges from the ABS brake and pressure test kit on one front and one rear bleeder screw.
• Apply 6895 kPa (1000 psi) to the front brake system.
• Is the pressure in the rear system 3516-4481 kPa (510-650 psi)?

BLEED the brake system. REFER to Bleeding - System in this section.

RETEST for normal operation.

No

GO to D2 .

• Key in ON position.
• Operate the brake pedal and note pedal feel.
• Does the pedal feel spongy?

GO to D3 .

No

REPAIR or INSTALL a new brake pedal as necessary. RETEST for normal operation.

• Inspect the brake pedal and bracket for binding, obstruction or damage.
• Is the brake pedal OK?

GO to D4 .

No

REPAIR or INSTALL new components as necessary. RETEST for normal operation.

• Inspect the calipers bolts, anchor plate bolts and anti-rattle springs for binding, damage, contamination and correct installation.
• Are the bolts and springs OK?

INSPECT the front wheel bearings for wear, damage and correct installation and the rear axle end play. CORRECT as necessary. RETEST for normal operation.

No

CORRECT as necessary. RETEST for normal operation.

• Check the power brake booster and brake master cylinder for correct installation and correct push rod adjustment.
• Are the power brake booster and the brake master cylinder OK?

GO to E2 .

No

CHECK for leakage of power steering fluid. ADD fluid as necessary.

• Check fluid level in power steering pump.
• Is level within specification?

GO to E3 .

No

INSTALL a new accessory drive belt.

• Check accessory drive belt tension and condition.
• Is the accessory drive belt OK?

GO to E4 .

No

INSTALL new hoses as necessary.

• Check power steering pressure hoses, power steering gear pressure hoses and power steering return hose for cracks or leaks.
• Do power steering pressure hose, power steering gear hose and power steering return hose check OK?

GO to E5 .

No

INSTALL new pedal linkage as necessary.

• Check brake pedal linkage for binding or sticking operation.
• Does pedal linkage check OK?

GO to E6 .

No

SET engine idle speed to specification.

REFER to Powertrain Control/Emissions Diagnosis (PC/ED) manual.

• Check engine idle speed against specifications.
• Is engine idle speed OK?

INSTALL a new power steering return hose.

No

GO to E7 .

• NOTE: The return hose from the oil cooler to the power steering reservoir has an in-line filter in the hose.
• Disconnect power steering return hose from power steering fluid cooler and power steering pump reservoir.
• Pass air through hose from the oil cooler end.
• Is hose plugged?

INSTALL a new power brake hydro-boost unit.

No

INSTALL a new power steering pump.

• Test power steering pump for correct flow and relief pressure.
• Is power steering pump operating correctly?

REMOVE obstructions or INSTALL a new hose.

No

GO to F2 .

• Check for obstructions in power steering return hose and connections between the power steering pump reservoir and between the power steering pump reservoir and the hydro-boost power brake booster.
• Are there any obstructions?

System OK.

No

INSTALL a new hydro-boost assembly.

• Have an assistant check the fluid in the power steering pump reservoir while rapidly applying the brake pedal approximately one inch.
• Does the fluid show any movement or spouting?

Hydro-boost is OK.

No

GO to G2 .

• Key in OFF position.
• Press and release brake pedal several times to deplete all hydraulic pressure from the hydro-boost power brake booster.
• Press and hold brake pedal with light pressure.
• Key in START position.
• Does the brake pedal fall slightly and hold, and is less pressure now required to hold brake pedal at the new position?

GO to G3 .

No

GO to G4 .

• With engine running, press and release brake pedal several times.
• Hold brake pedal down with medium pressure, 34-47 Nm (25-35 lb-ft).
• Does brake pedal move toward floor?

COMPLETE master cylinder By-Pass Condition Test in this section.

No

INSTALL new hoses and lines as necessary.

• Check for leaks at brake lines, including brake master cylinder and brake hose.
• Do components check OK?

GO to G5 .

No

REPAIR or INSTALL new hose and connections as necessary.

• Clean the hydro-boost power brake booster, power steering pressure hose, power steering gear pressure hose and power steering return hose and connection.
• Start engine and run at idle.
• Check hose connections for leakage.
• Do hose connections check OK?

GO to G6 .

No

INSTALL a new hydro-boost unit.

• Engine running at idle speed.
• CAUTION: Do not hold the brake pedal at 444 Nm (100 lb) force for more than 5 seconds at a time.
• Apply brake pedal with approximately 444 Nm (100 lb) force and hold.
• Check hydro-boost unit input seal, housing seal, accumulator seal, piston seal and spool plug seal for leakage.
• Is hydro-boost unit free of leaks?

Hydro-boost unit is OK.

No

INSTALL a new hydro-boost unit.

• Engine running at idle speed.
• CAUTION: Do not hold the brake pedal at 444 Nm (100 lb) force for more than 5 seconds at a time.
• Charge system to pressure by holding the steering wheel at stop or by pressing the brake pedal with approximately 444 Nm (100 lb) force.
• Key in OFF position.
• Wait five seconds.
• Press brake pedal and observe if there is any power brake reserve.
• Is there any power brake reserve?