B0402
Tachometer Circuit Malfunction
2000-2004 Porsche Boxster 2.7L H6
Low SeverityBodyGeneric (SAE)
Description
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
- Check RPM signal from PCM with scan tool
- Test tachometer stepper motor
- Inspect cluster circuit board
- Check wiring from PCM to cluster
Repair Notes
Replace instrument cluster stepper motor or circuit board.
Related Codes
Other Body Codes
- B0001Driver Frontal Stage 1 Deployment Control
- B0002Driver Frontal Stage 2 Deployment Control
- B0003Passenger Frontal Stage 1 Deployment Control
- B0004Passenger Frontal Stage 2 Deployment Control
- B0005Driver Knee Airbag Deployment Circuit
- B0006Passenger Knee Airbag Deployment Circuit
- B0010Driver Side Airbag Deployment
- B0011Driver Side Airbag Deployment Circuit Open
- B0012Driver Side Airbag Deployment Circuit Short to Ground
- B0013Driver Side Airbag Deployment Circuit Short to Battery
B0402 on Other Vehicles
Porsche 718 Boxster
2017-2024 2.0L H4 Turbo
Porsche 718 Boxster
2017-2024 2.0L Turbo H4
Porsche 718 Boxster GTS
2020-2024 4.0L H6
Porsche 718 Boxster S
2017-2024 2.5L Turbo H4
Porsche 718 Cayman
2017-2024 2.0L H4 Turbo
Porsche 718 Cayman
2017-2024 2.0L Turbo H4
Porsche 718 Cayman GT4
2019-2024 4.0L H6
Porsche 718 Cayman GTS
2020-2024 4.0L H6
Common Questions
What does code B0402 mean on a 2000-2004 Porsche Boxster?
B0402 stands for "Tachometer Circuit Malfunction". The tachometer gauge is not functioning or displays incorrect RPM readings.
What are the symptoms of B0402 on a Porsche Boxster?
Common symptoms of B0402 include: Tachometer reads zero, Tachometer needle erratic, Tachometer bouncing at idle, Gauge needle stuck.
What causes B0402 on a 2000-2004 Porsche Boxster?
Common causes of B0402 include: Instrument cluster stepper motor failure, Cluster circuit board fault, RPM signal issue from PCM, Wiring problem.