B0104high severityBody
Immobilizer Control Module Communication
on 2000 Acura RL 3.5L V6 · AWD
What this code means
The immobilizer control module is not communicating with the ECM/PCM. Both modules must agree before engine starting is allowed.
Symptoms
- Engine will not start
- Security light on
- No communication with immobilizer module
- Multiple no-start codes
Common causes
- Immobilizer module failure
- CAN bus wiring issue between modules
- ECM/PCM fault
- Power or ground issue to immobilizer module
Diagnostic steps
- Check CAN bus communication
- Test immobilizer module power and ground
- Scan both immobilizer and ECM for codes
- Check wiring between modules
- Try key relearn procedure
Repair notes
Repair CAN bus wiring or replace immobilizer control module. Modules may need to be paired.
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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