Internal Control Module Malfunction
2007-2016 Volvo S80 3.2L I6
Description
The ECM detected an internal hardware or software malfunction. The ECM self-diagnostic routines have identified a failure in one of its internal circuits or memory areas.
Symptoms
- Check Engine Light
- Various driveability issues
- Other fault codes may appear
- Intermittent problems
Common Causes
- ECM internal circuit failure
- ECM memory corruption
- Voltage spike or brown-out damage
- ECM software error
- Poor ECM ground connection
Diagnostic Steps
- Check all ECM power and ground connections
- Clear codes and verify if fault returns
- Update ECM software to latest version
- Test ECM supply voltage stability
- Replace ECM if internal fault confirmed
Repair Notes
Update ECM software; replace ECM if internal malfunction persists after reprogramming.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P1603 on Other Vehicles
Common Questions
What does code P1603 mean on a 2007-2016 Volvo S80?
P1603 stands for "Internal Control Module Malfunction". The ECM detected an internal hardware or software malfunction. The ECM self-diagnostic routines have identified a failure in one of its internal circuits or memory areas.
What are the symptoms of P1603 on a Volvo S80?
Common symptoms of P1603 include: Check Engine Light, Various driveability issues, Other fault codes may appear, Intermittent problems.
What causes P1603 on a 2007-2016 Volvo S80?
Common causes of P1603 include: ECM internal circuit failure, ECM memory corruption, Voltage spike or brown-out damage, ECM software error, Poor ECM ground connection.