Powertrain
Definition only
Lights the check engine lamp
P2A77: Alternative Fuel Hydraulic Pump Pressure Sensor Circuit Low
Standardized SAE J2012 code · P2Axx codes
What does P2A77 mean?
Voltage on the alternative fuel hydraulic pump pressure sensor signal line is below the expected window. Wire shorted to ground or sensor short.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Common causes
- High Signal wire shorted to ground
- Medium Internal sensor short
- Low Connector pins corroded - high contact resistance
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P2A77 on the same make and model first.
P2A77 in the community
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