Powertrain, generic (extended)

P2185 Engine Coolant Temperature Sensor 2 Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2185 is the high end of the sensor 2 circuit check. With an NTC thermistor a high signal stands for extreme cold, so the usual reason is an open circuit: a broken wire, an unplugged or corroded connector, or a sensor with an interrupted element; a short to voltage is rarer. GM (19OBDG03D) watches for a resistance in the order of 300 kOhm, the value at -60 °C, after 10 s of engine running or above -20 °C intake air, 5 s within 6 s, Type B. VW sets it at below -43 °C on the 2014 CC and above 4.92 V or 4.94 V on the Touareg. Audi issued a 2025 bulletin for the A4 and A5 family on P2185 at the radiator outlet sender G83. In bulletin 21-NA-149 GM traces it to a chafed harness. Low and erratic signals are P2184 and P2186.

Likely causes

Connector at sensor 2 unplugged, loose or corroded
Signal or ground wire of sensor 2 broken
Sensor element interrupted
Signal wire shorted to a voltage source

Symptoms

  • Check engine light
  • Fans run permanently as a safety measure
  • Low coolant or temperature warning without a real cause on some models

Repair estimate

DifficultyEasyDIY possible
Parts and labour€30–250
Time0.3–2 h

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

Parts involved

engine coolant temperature sensor 2sensor wiring

Related codes

P2184P2186P2182P2183P0118P01E6

References: gsi.ext.gm.com, static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov.