OBD-II Fault Code

P0197: Engine Oil Temperature Sensor Low

Meaning, symptoms, likely causes, diagnostic checks and repair guidance for P0197.

System family

Powertrain

Generic/SAE

Repair category

Electrical circuit / sensor

Use this category to narrow your checks before replacing parts.

Severity

Medium

Severity is a general guide. Confirm with scan-tool data and vehicle symptoms.

What P0197 usually means

Engine Oil Temperature Sensor Low.

Common symptoms

Check Engine light; Poor drivability or reduced fuel economy depending on fault

Likely causes

Low signal voltage; Weak power supply; High resistance/poor ground; Failed sensor

Diagnostic checks

Scan all modules and record freeze-frame data before clearing codes; Check battery voltage and related fuses; Check sensor reference voltage, ground and signal voltage

Repair guidance

Repair poor ground/power feed or replace confirmed faulty sensor

Verification after repair

Clear code, road-test through the same drive condition, then rescan

Note: Confirm vehicle make/model/year because manufacturer-specific codes can vary. A DTC identifies a circuit or system condition, not always the failed part.