DTC P0031 & DTC P0032: Condition

DTC P0031 is set when Engine Control Module (ECM) detects Heated Oxygen Sensor No. 1 (HO2S-1) heater circuit voltage input is higher than 13.99 volts while HO2S-1 heater is ON. DTC P0032 is set when ECM detects HO2S-1 heater circuit voltage input is lower than 11.72 volts while HO2S-1 heater is ON. MIL is illuminated when ECM detects malfunction during 2 consecutive drive cycles. Possible causes are:

• ECM malfunction.
• HO2S-1 heater circuit malfunction.
• HO2S-1 heater malfunction.