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DTC codes / P09xx · Transmission / P0941

P0941Hydraulic Oil Temperature Sensor Circuit Intermittent

P0941 indicates that the transmission control module (TCM) has detected an intermittent fault in the hydraulic oil temperature sensor circuit, which monitors the temperature of the transmission fluid. The computer sets this code when the sensor signal momentarily drops out or returns an implausible value, rather than failing completely.

SystemPowertrain
Code typeGeneric (all makes)
SeverityMedium
Fix difficultyIntermediate
AreaTransmission

Symptoms you may notice

  • Illumination of the check engine light or transmission warning light, often with no other noticeable symptoms.
  • Intermittent harsh or delayed shifting as the TCM loses accurate temperature data and defaults to a calculated value.
  • Occasional torque converter clutch engagement shudder or poor shift quality during warm-up.
  • A stored code that may clear itself after several drive cycles if the intermittent fault does not recur.
  • In rare cases, the transmission may enter limp mode (fixed gear) if the signal is lost for an extended period.

Common causes, most likely first

  1. Chafed, corroded, or loose wiring in the hydraulic oil temperature sensor circuit, especially at connectors or where the harness passes near heat sources.
  2. A failing hydraulic oil temperature sensor that intermittently opens or shorts internally when hot or cold.
  3. Poor electrical connection at the sensor pigtail or TCM connector, often due to water intrusion or vibration.
  4. A faulty transmission control module (TCM) or internal circuit issue, though this is less common.
  5. Low or contaminated transmission fluid that causes the sensor to read erratically under certain conditions.
  6. Aftermarket electrical accessories or poor grounds that introduce noise into the sensor signal.

How to diagnose and fix it

  1. Inspect the sensor wiring and connectors for damage, corrosion, or loose pins, and repair as needed.
  2. Check transmission fluid level and condition; service the fluid if it is low or contaminated.
  3. Use a scan tool to monitor the hydraulic oil temperature sensor live data while wiggling the harness and connectors to reproduce the intermittent fault.
  4. Perform a resistance test on the sensor at varying temperatures and compare to specifications; replace the sensor if it is out of range or erratic.
  5. Check for continuity and short-to-ground or short-to-power on the signal and return circuits between the sensor and TCM.
  6. If all external circuits and the sensor test good, suspect the TCM and perform pinpoint tests according to the manufacturer's service information before replacement.

Intermittent faults demand live data, not guesswork

  • A P0941 code often sets because of a momentary glitch in the sensor signal, so the sensor itself may test perfectly fine when the fault is not present; always road-test with a scan tool recording live data to catch the dropout.
  • Heat and vibration are common triggers for intermittent sensor circuit faults, so pay close attention to harness routing near exhaust components and check for stretched or pinched wires.
  • Some vehicles use the hydraulic oil temperature sensor as part of a combined sensor module; replacing just the sensor may not be possible, and the entire module may need replacement.
  • A weak battery or charging system can cause voltage spikes that confuse the TCM and set intermittent sensor codes; always verify battery and charging system health before condemning the sensor.
  • The code may be stored in history without illuminating the warning light if the fault occurred only once; do not clear it until you have verified the circuit is sound, or it may return.

Can I keep driving with P0941?

You can generally continue driving with a P0941 code because the fault is intermittent and the transmission often defaults to a safe strategy, but avoid heavy towing or aggressive driving until the circuit is repaired. If the transmission begins shifting harshly or enters limp mode, seek service promptly to prevent further damage.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

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