What does it mean?
P1471 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: EVAP Emission Control Leak Detection Pump Circuit Short to B+ .
Symptoms
- MIL on
- EVAP monitor never completes and readiness stays not ready
- Engine performance is usually normal
- The pump does not operate at all, because the driver can no longer pull the circuit low
- Possible fuel vapour odour if the vent path is affected
Likely causes
- Control wire shorted to a battery voltage source, typically where the harness is chafed against a power lead or metal edge
- Leak detection pump solenoid shorted internally and pulling the driver high
- Melted harness insulation near a hot exhaust component
- Moisture and corrosion bridging pins inside the pump connector
- Incorrect earlier repair or a spliced-in wire feeding constant voltage into the circuit
- Module driver damaged by the applied voltage
How to fix it
- Disconnect the pump and check the control wire for voltage with the key on; voltage present while the driver is off confirms a short to power
- Trace the harness along the tank and rear underbody looking for melted or abraded insulation
- Inspect the connector for moisture and corrosion bridging adjacent pins
- Measure solenoid resistance to identify an internal short
- Repair or reroute damaged wiring away from power leads and heat sources
- Replace the pump if it tests shorted, then confirm the module can still control the circuit
- Clear codes and complete an EVAP monitor drive cycle