Applicable Systems
OBD-II
Symptoms
The oxygen sensor heater circuit has a fault. The sensor may not reach operating temperature efficiently.
Possible Causes
- Heater element inside the O2 sensor open
- Heater circuit wiring open or shorted
- Heater relay or fuse failed
Troubleshooting Steps
- Step 1: Check O2 sensor heater resistance
Heater resistance within specification - Step 2: Test heater circuit wiring for continuity
Wiring has continuity - Step 3: Inspect heater relay and fuse
Relay and fuse functional
How to Reset
To reset: Clear the DTC after repairing the heater circuit or replacing the sensor.
Source: SAE J2012 OBD-II Diagnostic Trouble Codes, SAE International
Category: OBD-II