Chassis, generic

C0093 4WD/AWD Power Transfer Unit Temperature Sensor

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

Covers the temperature sensor of the power transfer unit, which lets the controller protect the AWD clutch from overheating. Sustained torque transfer, for example prolonged slip or towing, heats the clutch pack and its fluid; the controller reads this sensor and reduces or opens the coupling when temperature climbs too high. This code is set when the sensor signal is out of range, open, shorted or implausible. AWD coupling patents describe electronically controlled clutches whose controller monitors operating conditions, including temperature, to protect the hardware. A fault removes thermal protection and can force a safe default such as reduced engagement, and sets the AWD/4WD warning lamp; braking and ABS are unaffected. The entry follows the SAE J2012 generic definition and AWD coupling thermal management.

Likely causes

Temperature sensor out of range or failed
Harness or connector fault
Genuine clutch overheating event

Symptoms

  • AWD/4WD warning lamp on
  • Reduced AWD engagement for protection
  • No thermal protection of the coupling

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€150–1,400
Time1–4 h

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

Parts involved

ptu temp sensor

Related codes

C0090C0094C0091

References: patents.google.com, en.wikipedia.org.