DTC C0033 Subaru
Rear Air Fuel Ratio (A F) Sensor (Bank 1, Sensor 1) Heater Circuit Malfunction
Rear Air Fuel Ratio (A F) Sensor (Bank 1, Sensor 1) Heater Circuit Malfunction
Description
The execution time is continuous and the duration time is 2 seconds or more. Engine running and battery at 10 volts or more. No return signal HIGH is detected when the PCM output duty is less than 2%. Return signal does not change when the PCM output duty is more than 20% and less than 80%. No return signal LOW is detected when the PCM output duty is more than 8%. NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot.
Cause and Solution
Poor connections or loose terminals at the A F sensor (Sensor 1), the relay and the PCM Open or Short circuit between the A F sensors, the relay box or the PCM Faulty A F sensor (Sensor 1) Faulty PCM
Video Guide
Diagnostic Info
- DTC Code: C0033
- Brand: Subaru