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2003 FORD EXCURSION

7.3L V8 Power Stroke Diesel4WDAUTOMATICdieselturbo
5 active safety recalls on this vehicle — view recalls
Repairs0Labor590Torque3995Fluid9DTC636Battery1Maintenance0Recalls5
P3021high severityPowertrain

CVT Primary Pulley Speed Sensor Circuit

on 2003 Ford Excursion 7.3L V8 Power Stroke Diesel · 4WD

What this code means

The primary (input) pulley speed sensor in the CVT is reporting erratic or no signal. The TCM requires this signal for ratio control.

Symptoms

  • Check Engine Light
  • Transmission stuck in one ratio
  • Erratic shifting
  • Speedometer malfunction
  • Limp mode
  • Delayed engagement

Common causes

  • Faulty primary pulley speed sensor
  • Damaged tone ring
  • Sensor wiring damage
  • Contaminated sensor tip
  • TCM input circuit failure

Diagnostic steps

  1. Read primary pulley speed PID
  2. Inspect sensor connector and wiring
  3. Check tone ring condition
  4. Test sensor resistance and air gap
  5. Compare primary to secondary sensor readings

Repair notes

Replace primary pulley speed sensor. Inspect tone ring for damage or contamination.

Other Powertrain codes on this vehicle

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