MALFUNCTION OF INTAKE AIR TEMPERATURE SENSOR [LO]
(DTC CODE P0112 / DIAGNOSIS MONITOR CODE 17)

1. Set the starter key to the "LOCK" position and disconnect the intake air temperature sensor connector.
2. Measure resistance between the 1st and 2nd terminals of the intake-air temperature sensor connector (component side).

   
   

   
   

   Standard value

   Intake air temperature in measurement (ºC {ºF})	Resistance (kΩ)
   -20 {-4}	14.7
   20 {68}	2.0
   60 {140}	0.59

   

   If it is difficult to troubleshoot the connector itself, go to [3] Measuring resistance between terminals.

NO Fault in intake air temperature sensor

YES Proceed to [2] Measuring voltage between sensor terminals

1. Turn the starter key "ON" and measure voltage between the 1st and 2nd terminals of the intake air temperature sensor connector (vehicle harness side).

   
   

   
   

   Standard value: 4.5-5.5 V

 

NO Go to [3] Measuring resistance between terminals.	YES Disconnection of the harness

1. Set the starter key to the "LOCK" position and connect the signal check harness.
2. Disconnect the signal check harness connectors from the ECU and measure resistance between the terminals E47 and E78.

   
   

   

   ECU terminal No.	Description of terminal
   E47	Intake air temperature sensor SIG
   E78	GND

   Standard value

   Intake air temperature in measurement (ºC {ºF})	Resistance (kΩ)
   -20 {-4}	14.7
   20 {68}	2.0
   60 {140}	0.59

 

NO Fault in intake air temperature sensor	YES Proceed to [4] Measuring voltage between terminals

1. Connect the signal check harness connectors to the ECU.
2. Disconnect the signal check harness connectors from the vehicle harness.
3. Turn the starter key "ON" and measure voltage between the terminals E47 and E78.

   
   

   
   

   Standard value: 4.5-5.5 V

 

NO Fault in engine ECU and/or ECU connectors	YES Disconnection of the harness

1. Confirm the DTC P0112 is inactive

   • Start the engine and let it idling condition.
   • Verify the DTC P0112 is inactive.

   

2. DTC Clear

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

   

P0112 is reoccur: Return to first process Other DTC appear: Refer to concerned Trouble shooting

Complete