P0052 — HO2S Heater Control Circuit High Bank 2 Sensor 1

HO2S Heater Control Circuit High Bank 2 Sensor 1. Basic catalogue definition; diagnostic details have not yet been reviewed.

Affected system: Powertrain

Symptoms

• The check-engine lamp may illuminate because the heated oxygen sensor at bank 2, sensor 1 has a high heater control circuit signal.
• Driving behaviour can remain unchanged; some cars may show delayed emissions-control readiness or higher consumption.

Possible causes

• Failure in the heater element of the oxygen sensor at bank 2, sensor 1.
• Heat-damaged wiring, open or shorted conductors, corroded connectors or an affected heater fuse/relay.
• Control-module output fault is a less common possibility only after other tests.

What to check

• Record P0052 and related DTCs; confirm the precise location of bank 2, sensor 1 using the OEM layout.
• With ignition off and the exhaust cool, inspect the correct sensor harness, connector, fuses and wiring routing.
• Compare supply, ground and commanded heater operation with the vehicle-specific wiring diagram and diagnostic tool.
• With the connector disconnected, measure heater resistance only using the applicable OEM test method and temperature conditions.
• Check for circuit opens, shorts and voltage drops; do not apply direct battery power to a heater without OEM authorization.
• Repair confirmed harness/fuse issues or replace a heater sensor only if its own tests fail; confirm DTC and monitor readiness afterward.

Also written as: P0052-00, P005200, PO052 (some scan tools add the fault-type byte, e.g. -00).