C1390  ABNORMALITY OF POWER SUPPLY VOLTAGE

1. Set the starter switch to "ON", measure the voltage between 4th terminal of the 24 pin connector of ECU and 2nd terminal of the 31 pin connector of ECU. (Leaving the connector connected with ECU.)
   Standard: 20-32V
   
   
   　

Abnormality of the power supply circuit.

Abnormality of the ECU.

1. Confirm the DTC C1390 is inactive

   • Start the engine and let it idling condition.
   • Verify the DTC C1390 is inactive.

   

2. DTC Clear

   • Clear the DTC with Hino DX
   • Confirm the same DTC is not reoccurred

   

C1390 is reoccur: Return to first process Other DTC appear: Refer to concerned Trouble shooting

Complete