B0401moderate severityBody
Speedometer Circuit Malfunction
on 1997 Acura RL 3.5L V6 · AWD
What this code means
The speedometer gauge is not functioning or is displaying incorrect speed readings.
Symptoms
- Speedometer reads zero while driving
- Speedometer reads erratically
- Speedometer needle bouncing
- Cruise control may not work
Common causes
- Faulty vehicle speed sensor
- Instrument cluster stepper motor failure
- Cluster circuit board fault
- Speed signal wiring issue
Diagnostic steps
- Check speed sensor signal with scan tool
- Compare GPS speed to speedometer
- Test cluster stepper motor
- Check speed sensor wiring
- Scan for related speed sensor codes
Repair notes
Replace speed sensor or instrument cluster stepper motor. If cluster board is faulty, replace or repair cluster.
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Other Body codes on this vehicle
B0001
Driver Frontal Stage 1 Deployment Control
B0001
Driver Frontal Stage 1 Deployment Control
B0002
Driver Frontal Stage 2 Deployment Control
B0002
Driver Frontal Stage 2 Deployment Control
B0003
Passenger Frontal Stage 1 Deployment Control
B0003
Passenger Frontal Stage 1 Deployment Control
B0004
Passenger Frontal Stage 2 Deployment Control
B0004
Passenger Frontal Stage 2 Deployment Control
B0005
Driver Knee Airbag Deployment Circuit
B0005
Driver Knee Airbag Deployment Circuit