C1266 Exhaust Retarder Prevention Signal Circuit

1. Disconnect the skid control ECU connector and the ECM connector.
   
2. Measure the resistance according to the value (s) in the table below.
   
   
   Standard resistance:

   Tester Connection	Condition	Specified Condition
   S13-10 (EXO) - E24-30 (ABS)	Always	Below 1Ω
   S13-10 (EXO) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

[2] INSPECT ECM (ECU INPUT)

1. Reconnect the ECM connector.
2. Turn the ignition switch to the ON position.
3. Measure the voltage according to the value (s) in the table below.
   
   
   Resistance voltage:

   Tester Connection	Switch Condition	Specified Condition
   E24-30 (ABS) - Body ground	Ignition switch ON	18 to 32 V

REPLACE ECM (See Pub No.SI-YXZE16D-1 ( Chapter ES))

[3] INSPECT SKID CONTROL ECU (ECM INPUT)

1. Turn the ignition switch off.
2. Reconnect the skid control ECU connector.
3. Turn the ignition switch to the ON position.
4. Measure the voltage according to the value (s) in the table below.
   
   
   
   Standard voltage:

   Tester Connection	Switch Condition	Specified Condition
   S13-10 (EXO) - Body ground	Ignition switch ON	18 to 32 V

REPLACE SKID CONTROL ECU

[4] RECONFIRM DTC

1. Turn the ignition switch off.
2. Clear the DTC (See Pub. No. S1-YXZE05A, page 05-108).
3. Drive the vehicle at a speed of 6 km/h (4 mph) or more for 10 seconds or more.
4. Check if the same DTC is recorded (See Pub. No. S1-YXZE05A, page 05-108).
   
   Result:

   Result	Proceed to
   DTC (C1266) is not output	A
   DTC (C1266) is output	B

A CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (See DIAGNOSIS SYSTEM)

B REPLACE SKID CONTROL ECU

1. Confirm the DTC C1266 is inactive

   • Start the engine and let it idling condition.
   • Verify the DTC C1266 is inactive.

   

2. DTC Clear

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

   

C1266 is reoccur: Return to first process Other DTC appear: Refer to concerned Trouble shooting

Complete