MechanicDB
Fault Family System: Powertrain (P-Codes) 6 SAE Codes

O2 Signal Shorted To Heater

Diagnostic & Technical Explanation
P2231 (O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 1 Sensor 1) means the ECM has detected the oxygen sensor's signal wire carrying heater-circuit voltage — an internal short between the two circuits inside the sensor body, or crossed/melted wiring in the shared harness section. Internal breakdown of the sensor's insulation as it ages thermally is the most common cause; the telltale of a harness cause instead is the code appearing on multiple sensors that share one melted loom section near the exhaust.

These 6 diagnostic trouble codes share one detection mechanism and one repair path, which is why MechanicDB groups them into a single authored fault family rather than repeating the same explanation 6 times.

Codes in this family (6)

CodeDefinitionRepair coverage
P2231O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 1 Sensor 13 ranked fixes
P2232O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 1 Sensor 23 ranked fixes
P2233O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 1 Sensor 33 ranked fixes
P2234O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 2 Sensor 13 ranked fixes
P2235O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 2 Sensor 23 ranked fixes
P2236O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 2 Sensor 33 ranked fixes

What this page does not show

This page publishes the fault mechanism and the code index. The licensed dataset adds, for every one of the 15,886 codes, the full authored repair set (56,729 procedures in total) with the fields deliberately withheld here: