P0512moderate severityPowertrain
Starter Request Circuit
on 2009 Audi A8 4.2L V8 · AWD
What this code means
The PCM detects a fault in the starter request circuit. This can affect cranking and engine starting.
Symptoms
- No-crank or hard start
- Check engine light on
- Intermittent starting issues
Common causes
- Faulty starter relay circuit
- Wiring fault in start request line
- Ignition switch fault
- Poor connector contact
Diagnostic steps
- Scan for starting-related codes
- Inspect starter request wiring
- Test ignition switch signal
- Check relay and connector integrity
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