MALFUNCTION OF ENGINE RETARDER 1 [OPEN/GND SHORT-CIRCUIT]
(DTC CODE P1462 / DIAGNOSIS MONITOR CODE 55)

1. Set the starter key to the "LOCK" position and connect the signal check harness.
2. Turn the starter key "ON" and measure voltage between the terminals E4 and E22.

   

    

   ECU terminal No.	Description of terminal
   E4	Engine retarder solenoid valve power supply
   E22	Engine retarder solenoid valve 1

   Standard value: 19 V or more

NO Go to [2] Measuring continuity between terminals.	YES Fault in engine ECU and/or ECU connectors

1. Set the starter key to the "LOCK" position.
2. Disconnect the injector cluster connector located on the front side of the cam housing.
3. Measure resistance between the 16th terminal of the injector harness integrated connector (a male connector) of the cam housing side and a reasonable GND such as an engine body.
   

   

   Standard value: ∞ Ω

NO GND short-circuit in harness and/or connector, fault in actuator relay	YES Proceed to [3] Inspecting the engine retarder solenoid valve

1. Measure resistance between the 14th and 16th terminals of the injector harness integrated connector (a male connector) of the cam housing side.

   

    

   Standard value: Approximately 34-44 Ω

    

2. If the standard value is not met in the step 1 above, open the engine head and disconnect a harness from the engine retarder solenoid valve. Measure resistance between terminals of the solenoid valve.

Standard value: Approximately 34-44 Ω

NO Fault in engine retarder solenoid valve	YES Fault in harness and/or connector

1. Confirm the DTC P1462 is inactive

   • Start the engine and let it idling condition.
   • Verify the DTC P1462 is inactive.

   

2. DTC Clear

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

   

P1462 is reoccur: Return to first process Other DTC appear: Refer to concerned Trouble shooting

Complete