B0421moderate severityBody
ABS Warning Lamp Circuit
on 1997 Acura RL 3.5L V6 · AWD
What this code means
Malfunction in the ABS warning lamp circuit. The lamp may not illuminate or may stay on incorrectly.
Symptoms
- ABS light does not come on during bulb check
- ABS light always on
- Cannot determine ABS system status
- Light flickering
Common causes
- Burnt out lamp
- Cluster fault
- ABS module lamp driver failure
- Wiring issue
Diagnostic steps
- Check lamp during key-on bulb check
- Scan ABS module for codes
- Test lamp drive circuit
- Inspect wiring from ABS module to cluster
Repair notes
Replace ABS warning lamp or repair wiring circuit.
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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