P2E78

Hybrid/EV Battery Pack Coolant Temperature Sensor D Circuit Intermittent/Erratic

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$17–56 (est.)

Symptoms

Unstable battery coolant temperature readings
Reduced performance of the hybrid system
Check Engine Light Illuminated
Possible reduction in vehicle power
Activation of emergency operation

Causes

Poor contact in the sensor connector
Wiring harness damage
Temperature sensor malfunction
Corrosion of electrical contacts
Problems with the battery control unit

How to Fix

Check connections and sensor connector
Inspect the wiring harness for damage
Test the temperature sensor
Clean contacts from corrosion
Replace sensor if necessary

Related codes

P2E77 P2E79 P0A7F