Common Symptoms
- Check engine light illuminated
- Multiple sensor-related fault codes stored simultaneously
- Engine may run in limp mode with reduced power
- Poor engine performance or rough running
- Intermittent stalling or hesitation during acceleration
Most Likely Root Causes
- Open circuit in sensor reference voltage supply wiring
- Damaged or corroded wiring harness connector
- Failed powertrain control module (PCM) internal voltage regulator
- Short to ground in sensor reference voltage circuit
- Corroded or loose ground connections affecting sensor circuit
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Component Location
The sensor reference voltage circuit originates from the powertrain control module and supplies multiple sensors throughout the engine compartment.
Manufacturer Notes
Many manufacturers use multiple sensor reference voltage circuits labeled A, B, and C to supply different sensor groups.
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