OBD-II code · Powertrain (generic)
P0538 A/C Evaporator Temperature Sensor Circuit High
The evaporator temperature sensor signal voltage is above the upper diagnostic threshold. Typically open circuit or short to power.
Is it safe to drive with P0538?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelySensor open internally
- PossibleWiring open or disconnected
- Less likelyConnector pins corroded - high contact resistance
Repair at a glance
- Difficulty
- Easy
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.3–1.5 h
- Emissions test
- Usually unaffected
- Parts involved
- AC Evaporator Temp Sensor, Sensor Wiring
Related codes
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.