Back to 2002 Mercedes-Benz SL

2002 MERCEDES-BENZ SL

3.0L I6RWDAUTOMATICgas
Repairs0Labor593Torque3658Fluid7DTC698Battery1Maintenance0Recalls0
B0402low severityBody

Tachometer Circuit Malfunction

on 2002 Mercedes-Benz SL 3.0L I6 · RWD

What this code means

The tachometer gauge is not functioning or displays incorrect RPM readings.

Symptoms

  • Tachometer reads zero
  • Tachometer needle erratic
  • Tachometer bouncing at idle
  • Gauge needle stuck

Common causes

  • Instrument cluster stepper motor failure
  • Cluster circuit board fault
  • RPM signal issue from PCM
  • Wiring problem

Diagnostic steps

  1. Check RPM signal from PCM with scan tool
  2. Test tachometer stepper motor
  3. Inspect cluster circuit board
  4. Check wiring from PCM to cluster

Repair notes

Replace instrument cluster stepper motor or circuit board.

Other Body codes on this vehicle

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