C0221moderate severityChassis
EPS Control Module Voltage Low
on 2007 Volvo S80 3.2L I6 · AWD
What this code means
The EPS module supply voltage has dropped below the minimum operating threshold.
Symptoms
- EPS warning light
- Power steering assist reduced
- Assist cuts out during electrical load
- Steering heavy at idle with AC on
Common causes
- Low battery voltage
- Weak alternator
- High resistance in EPS power supply wiring
- Corroded battery terminals
- Undersized wiring for EPS current demand
Diagnostic steps
- Measure battery voltage at rest and running
- Test alternator output under load
- Check voltage at EPS module connector
- Inspect battery terminals and cable ends
- Test EPS power supply fuse and connections
Repair notes
Repair charging system. Clean battery connections. Verify adequate wire gauge to EPS module.
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