What it means
The hydraulic oil temperature sensor reports a circuit fault. Oil temperature feedback for hydraulic system is unreliable.
At a glance
- Usually lights the check-engine light
How it works
The hydraulic oil temperature sensor reports fluid temperature to the TCM, which uses it when controlling the transmission. P0937 indicates a fault in the sensor circuit, so the module cannot rely on the temperature feedback; this is distinct from a signal specifically identified as too low, too high, or outside its expected range.
Common causes
Most likely first.
- Temperature sensor failed
- Wiring fault
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
How to diagnose it
- Record freeze-frame data and compare the live hydraulic oil temperature reading with ambient conditions before starting and as the transmission warms.
- Inspect the temperature sensor connector and harness for disconnection, corrosion, damaged insulation, or broken wires.
- Check the sensor circuit's signal, reference or supply, and ground connections against the manufacturer's wiring information.
- If the circuit is intact, test the temperature sensor and its response as the transmission warms, using the manufacturer's procedure.
- Repair the confirmed circuit or sensor fault, then recheck live temperature data and confirm the code does not return.
Common fixes
- Reconnect or clean a loose or corroded temperature sensor connector.
- Repair damaged wiring in the hydraulic oil temperature sensor circuit.
- Replace the temperature sensor if it fails the manufacturer's circuit or response checks.
Can I keep driving?
If shifting remains normal, limit driving and watch for transmission warnings or changes in shift quality, since the TCM lacks reliable oil temperature feedback. Stop driving if the transmission slips, shudders, or enters limp mode.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.