Circuit Description

1999 GMC Forward Control 4.3 W, StandardSECTION Circuit Description

As a toothed ring passes by the Wheel Speed Sensor (WSS), changes in the electromagnetic field cause the wheel speed sensor to produce an AC voltage signal. Voltage signal frequency and amplitude are proportional to wheel speed. The magnitude of this signal is directly related to wheel speed and proximity of wheel speed sensor to toothed ring, often referred to as the air gap.

Conditions for setting DTC:

  • No output signal from left front wheel sensor for one second.
  • Excessive left front wheel speed sensor resistance for one second.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
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  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.