Common Symptoms
- Check Engine Light illuminated
- Multiple sensor fault codes stored simultaneously
- Engine may run rough or stall intermittently
- Poor fuel economy or hesitation during acceleration
- Sensors may provide erratic readings or default values
- Vehicle may enter limp mode or reduced power mode
Most Likely Root Causes
- Short to ground in sensor reference voltage circuit wiring
- Damaged or corroded wiring harness or connectors
- Failed engine control module internal voltage regulator
- Multiple sensor failures causing excessive current draw
- Water intrusion or corrosion in ECM connector
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Component Location
The sensor reference voltage circuit originates from the engine control module and distributes to multiple sensors throughout the engine bay.
Manufacturer Notes
This code indicates a problem with the five-volt reference circuit that powers multiple sensors, and often affects throttle position, MAP, and other critical sensors simultaneously.
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