P0031 is set when open or short to ground in Lambda sensor control circuit is detected for more than 5.0 sec. at Lambda sensor heater control condition. This code is due to 1)open or short to ground in heater control circuit or 2)Lambda sensor heater internal short.
Item | Detecting Condition | Possible Cause | |
DTC Strategy |
•
Open or short to ground in Lambda Sensor Unit Heater Powerstage | 1. Open or short to ground in Lambda Sensor Unit Heater Circuit 2. Faulty Lambda Sensor Unit | |
Enable Conditions |
•
Engine running | ||
Threshold Value |
•
Open or short to ground in Lambda Sensor Unit Heater Circuit | ||
Fail Safe | Fuel Cut |
•
NO | |
EGR Off |
•
NO | ||
Fuel Limit |
•
NO | ||
Check Lamp |
•
NO | ||
