TorqueMech OBD Code Guide
P0178 - Fuel Composition Sensor Circuit Low Input
The fuel composition sensor signal is lower than expected.
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Read code pattern
Check likely system
Estimate after confirmation
Code Overview
The fuel composition sensor signal is lower than expected.
Common Causes
- Sensor fault
- Short to ground
- Wiring damage
Diagnostic Steps
- Inspect the harness for chafing
- Check signal voltage and reference voltage
- Confirm connector fit and terminal condition
Related OBD Codes
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Next Steps
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