P2C66

Hybrid/EV Electronics Coolant Pump A Underspeed

Severity

🔴 High

Can you drive?

Do not drive — repair immediately

Approx. repair cost

$56–167 (est.)

Symptoms

Overheat warning on dashboard
Hybrid system power reduction
Cooling pump noises
Overheating of electronic components
Check Engine Light Illuminates

Causes

Cooling pump malfunction
Problems with wiring or connectors
Low coolant level
Faulty relay or fuse
Problems with the pump control ECU

How to Fix

Check the level and condition of the coolant
Diagnose the electrical circuit of the pump
Check fuses and pump relays
Test or replace the cooling pump
Check error codes in the hybrid system ECU

Related codes

P2C65 P2C67 P0A80