B0401moderate severityBody
Speedometer Circuit Malfunction
on 1997 Volvo 850 2.4L I5 · FWD
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.
Other Body codes on this vehicle
B0001
Driver Frontal Stage 1 Deployment Control
B0002
Driver Frontal Stage 2 Deployment Control
B0003
Passenger Frontal Stage 1 Deployment Control
B0004
Passenger Frontal Stage 2 Deployment Control
B0005
Driver Knee Airbag Deployment Circuit
B0006
Passenger Knee Airbag Deployment Circuit
B0010
Driver Side Airbag Deployment
B0011
Driver Side Airbag Deployment Circuit Open
B0012
Driver Side Airbag Deployment Circuit Short to Ground
B0013
Driver Side Airbag Deployment Circuit Short to Battery