P0231high severityPowertrain
Fuel Pump Secondary Circuit Low
on 1998 Audi A8 3.7L V8 · AWD
What this code means
Low voltage in the fuel pump secondary (output) circuit.
Symptoms
- Engine stalling
- No start
- Loss of power at high RPM
Common causes
- Fuel pump failing
- Corroded connector
- High resistance wiring
- Weak battery during cranking
Diagnostic steps
- Test voltage at pump connector
- Check connector
- Measure current draw
Repair notes
Replace fuel pump or repair wiring.
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