P01BA Engine Oil Temperature Sensor B Range/Performance

The engine oil temperature sensor B is an NTC thermistor fed with 5 V through a resistor: the hotter the oil, the lower the signal voltage. The engine module uses the oil temperature for variable cam timing (Ford disables it with cold oil or a sensor fault), engine protection and the oil life monitor; many engines have no such sensor and use a calculated oil temperature instead. Sensor B is a second oil temperature sensor whose position is defined by the manufacturer. P01BA is the plausibility fault of sensor B, the counterpart of P0196 – presumably a cold-start comparison, a warm-up check or a comparison with sensor A or a model, as GM documents for sensor A. No manufacturer document using the B-sensor codes was found, so it is unclear who fits a sensor B; the description follows sensor A and CARB's circuit monitoring requirement.

Likely causes

Symptoms

• Check engine light on (depending on manufacturer)
• Implausible oil temperature values in scan data
• Usually no driving symptoms

Repair estimate

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

Related codes

References: law.cornell.edu, gsi.ext.gm.com.