What does it mean?
P1180 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Linear O2 Sensor / Pump Current Short to B+ .
Symptoms
- Check engine light on, usually straight after starting
- Fuel control switches to a default map, so the mixture is no longer corrected
- Rough idle, hesitation and reduced power
- Higher fuel consumption and a strong exhaust smell
- Additional oxygen sensor codes on the same bank
- Sensor heater fuse may blow repeatedly
Likely causes
- Harness chafed through to a battery-fed wire, typically where the sensor loom crosses the engine or passes a bracket
- Water, road salt or corrosion inside the sensor connector bridging the pump line to a supply pin
- Internal short in the sensor between the pump cell and its heater supply
- Incorrect or damaged replacement sensor with mismatched pin assignment
- Melted insulation where the harness has rested against the exhaust or turbocharger
- Poor previous repair: a splice or crimp shorting to another circuit
- Rarely, a failed module output stage holding the line high
How to fix it
- Disconnect the sensor and, with the ignition on, measure voltage on the pump current pin of the harness; battery voltage there proves the short
- With the module connector also removed, measure resistance between the pump line and known supply circuits
- Inspect the entire sensor harness for chafing, melted insulation and previous splices
- Open and dry the connector, checking for corrosion and moisture tracking between pins
- Repair or replace the damaged harness section and re-route it away from heat and sharp edges
- Check the sensor's internal resistances against specification and replace it if it is internally shorted
- Clear codes and confirm normal sensor operation in live data on a road test