Circuit/System Verification

Vehicle ON, observe the scan tool ECM Engine Coolant Temperature (ECT) parameter in freeze frame data.
Verify the Engine Coolant Temperature parameter was below 125°C (257°F) when the DTC set.
- If the ECT was 125°C (257°F) or greater when the DTC set
  Refer to Symptoms - Engine Cooling and correct that concern first.
- If the ECT was below 125°C (257°F) when the DTC set
Inspect for proper coolant level in the hybrid cooling system reservoir.
- If coolant level is low
  Refer to Hybrid Cooling System Loss of Coolant (Power Electronics) , Hybrid Cooling System Loss of Coolant (Battery) .
- If coolant level is OK
Inspect the hybrid/EV cooling system radiator for debris or obstruction.
- If a concern is found
  Repair or replace the restricted or damaged components as necessary.
- If no concern is found
Inspect for proper operation of all hybrid/EV system coolant pumps. Refer Hybrid/EV Electronics Cooling Diagnostic .
- If a concern is found
  Repair or replace the coolant pumps as necessary.
- If no concern is found
Command the cooling fans through all operating speeds.
- If the cooling fans do not operate in all speeds
  Refer to Hybrid/EV Electronics Cooling Diagnostic .
- If the cooling fans operate in all speeds
All OK