MALFUNCTION OF ENGINE SUB REVOLUTION SENSOR
(DTC CODE P0340 / DIAGNOSIS MONITOR CODE 12)

1. Set the starter key to the "LOCK" position and connect the signal check harness.
2. Disconnect the engine sub revolution sensor connector.
3. Turn the starter key "ON" and measure voltage between the 3rd and 2nd terminals of the engine sub revolution sensor connector (vehicle harness side).
   
   
   
   
   Standard value: 4.5-5.5 V

NO Go to [2] Measuring voltage between terminals.	YES Go to [3] Measuring an input waveform of the engine ECU.

1. Measure voltage between the terminals E73 and E54.
   

   

   ECU terminal No.	Description of terminal
   E54	G GND
   E73	G SIG

   Standard value: 4.5-5.5 V

NO Fault in engine ECU and/or connectors	YES Faulty harness

1. Set the starter key to the "LOCK" position and connect the engine sub revolution sensor connector.
2. Start and then idle the engine.
3. Measure voltage between the terminals E54 and E73.

   

   ECU terminal No.	Description of terminal
   E54	G GND
   E73	G SIG

   Standard: Pulse waveform of 0 ↔ 5 V

    

4. After measurement, stop the engine.

    

NO Go to [4] Measuring resistance between terminals.	YES Fault in engine ECU and/or ECU connectors

1. Keep the engine sub revolution sensor connector connected.
2. Measure resistance between the terminal E73 and the 1st terminal of the engine sub revolution sensor connector (vehicle harness side).
   

   
   

   

   This diagram shows the engine sub revolution sensor connector as viewed from the connecting face.

   Standard value: 2 Ω or less

NO Faulty harness	YES Fault in engine sub revolution sensor

1. Confirm the DTC P0340 is inactive

   • Start the engine and let it idling condition.
   • Verify the DTC P0340 is inactive.

   

2. DTC Clear

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

   

P0340 is reoccur: Return to first process Other DTC appear: Refer to concerned Trouble shooting

Complete