P0938Hydraulic Oil Temperature Sensor Range/Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- By J2012 wording the hydraulic oil temperature reading is electrically valid but implausible, for example frozen, rising too slowly after a cold start or disagreeing with other temperature values. Ferrari uses P0938 on its DCT for the radiator outlet and gearbox inlet oil temperature sensor, but describes it in its bulletin as no signal, an electrical fault rather than a plausibility check; the code is read in the NCR gearbox ECU. CARB asks for rationality checks on temperature inputs. P0937 is the general circuit fault, P0939 and P0940 the low and high faults, P0941 intermittent. A wrong temperature value leads to poorly matched clutch and shift pressures and may limit the cooling strategy.
- What you may notice
- Gearbox warning light on
- Shift and clutch quality inconsistent with operating temperature
- Likely causes
- LikelyTemperature sensor drifting or reacting sluggishly
- PossibleSignal lost through connector or wiring fault (as in Ferrari's no-signal case)
- RareReal temperature anomaly from a cooler or thermostat fault
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.