Fault code index · medium
P0052
HO2 Sensor heater control circuit high current – bank 2, upstream (2/1)
HO2 Sensor heater control circuit high current – bank 2, upstream (2/1)
Documented for: 2.0L gasoline; 2.5L/3.0L gasoline · System(s): EMS EOBD, EMS OBD II · Factory MIL flag: 2 · Default action: ECM Default: –Bank 2 closed loop fuel metering and adaptive fuel metering inhibited –Canister purge inhibited –Bank 2 upstream HO2S heater control circuit switched off.
Common causes
- HO2 Sensor 2/1 heater control circuit: short circuit to ground HO2 Sensor 2/1 heater ground circuit(s) fault (EN65-052, EN65-078) HO2 Sensor 2/1 heater failure
- HO2 Sensor 2/1 heater control circuit: short circuit to ground HO2 Sensor 2/1 heater ground circuit(s) fault (EN16-081, EN16-082) HO2 Sensor 2/1 heater failure
Quick checks
- Confirm freeze-frame and conditions when the code set
- Inspect connectors, grounds, and harness for the circuit named in the code
- Compare live sensor values vs expected (unplugged/biased sensors are common)