Fault Family System: Powertrain (P-Codes) 34 SAE Codes

O2 Heater Circuit

Diagnostic & Technical Explanation

Code P0030 (HO2S Heater Control Circuit Bank 1 Sensor 1) sets when the ECM detects an open, shorted, or out-of-spec resistance in the internal heater element of an oxygen sensor, or the heater fails to bring the sensor to operating temperature within the expected time. This is almost always a degraded heater element inside the O2 sensor itself, though a blown fuse, relay, or chafed heater wiring can also be responsible.

These 34 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 34 times.

Codes in this family (34)

Code	Definition	Repair coverage
P0030	HO2S Heater Control Circuit Bank 1 Sensor 1	3 ranked fixes
P0031	HO2S Heater Control Circuit Low Bank 1 Sensor 1	3 ranked fixes
P0032	HO2S Heater Control Circuit High Bank 1 Sensor 1	3 ranked fixes
P0036	HO2S Heater Control Circuit Bank 1 Sensor 2	3 ranked fixes
P0037	HO2S Heater Control Circuit Low Bank 1 Sensor 2	3 ranked fixes
P0038	HO2S Heater Control Circuit High Bank 1 Sensor 2	3 ranked fixes
P0042	HO2S Heater Control Circuit Bank 1 Sensor 3	3 ranked fixes
P0043	HO2S Heater Control Circuit Low Bank 1 Sensor 3	3 ranked fixes
P0044	HO2S Heater Control Circuit High Bank 1 Sensor 3	3 ranked fixes
P0050	HO2S Heater Control Circuit Bank 2 Sensor 1	3 ranked fixes
P0051	HO2S Heater Control Circuit Low Bank 2 Sensor 1	3 ranked fixes
P0052	HO2S Heater Control Circuit High Bank 2 Sensor 1	3 ranked fixes
P0053	HO2S Heater Resistance Bank 1 Sensor 1	3 ranked fixes
P0054	HO2S Heater Resistance Bank 1 Sensor 2	3 ranked fixes
P0055	HO2S Heater Resistance Bank 1 Sensor 3	3 ranked fixes
P0056	HO2S Heater Control Circuit Bank 2 Sensor 2	3 ranked fixes
P0057	HO2S Heater Control Circuit Low Bank 2 Sensor 2	3 ranked fixes
P0058	HO2S Heater Control Circuit High Bank 2 Sensor 2	3 ranked fixes
P0059	HO2S Heater Resistance Bank 2 Sensor 1	3 ranked fixes
P0060	HO2S Heater Resistance Bank 2 Sensor 2	3 ranked fixes
P0061	HO2S Heater Resistance Bank 2 Sensor 3	3 ranked fixes
P0062	HO2S Heater Control Circuit Bank 2 Sensor 3	3 ranked fixes
P0063	HO2S Heater Control Circuit Low Bank 2 Sensor 3	3 ranked fixes
P0064	HO2S Heater Control Circuit High Bank 2 Sensor 3	3 ranked fixes
P00D1	HO2S Heater Control Circuit Range/Performance Bank 1 Sensor 1	3 ranked fixes
P00D2	HO2S Heater Control Circuit Range/Performance Bank 1 Sensor 2	3 ranked fixes
P00D3	HO2S Heater Control Circuit Range/Performance Bank 2 Sensor 1	3 ranked fixes
P00D4	HO2S Heater Control Circuit Range/Performance Bank 2 Sensor 2	3 ranked fixes
P0135	O2 Sensor Heater Circuit Bank 1 Sensor 1	3 ranked fixes
P0141	O2 Sensor Heater Circuit Bank 1 Sensor 2	3 ranked fixes
P0147	O2 Sensor Heater Circuit Bank 1 Sensor 3	3 ranked fixes
P0155	O2 Sensor Heater Circuit Bank 2 Sensor 1	3 ranked fixes
P0161	O2 Sensor Heater Circuit Bank 2 Sensor 2	3 ranked fixes
P0167	O2 Sensor Heater Circuit Bank 2 Sensor 3	3 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:

Procedures 2..n after the first-listed procedure
Aftermarket parts cost ranges in USD (est_parts_cost_min/max_usd)
Professional labor-hour estimates (est_labor_hours)
Step-by-step diagnostic and repair instructions
Replacement-part mappings and catalog lookups
6,637 manufacturer-specific OEM codes across 32 makes ($149 tier)

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