Symptom of malfunction |
|
Output limit, etc. | Output limit |
Malfunction indicator light | Light on |
Multi information | Engine system failure (red) ↔ Stop the vehicle in the safe area. |
Possible cause of malfunction | Malfunction of injector solenoid valve drive system common 1 (GND short-circuit) |
Detail
- Set the starter key to the "LOCK" position and connect the signal check harness.
- Disconnect the signal check harness connectors from the ECU.
- Turn the starter key "ON" and measure voltage between the ECU case GND and a terminal of the signal check harness as listed below.
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Diagnosis code Terminal subject to resistance measurement DTC code Diagnosis monitor code P121168 E35, E36, E37ECU case GND P121468 E19, E20, E60ECU case GND
Standard value: 1 V or less
NO
Go to [2] Measuring voltage between injector terminals.YES
Go to [3] Measuring resistance between terminals.
Detail
- Set the starter key to the "LOCK" position and disconnect the injector harness integrated connector from the cylinder head.
- Turn the starter key ON and measure voltage between the ECU case GND and a terminal of the injector cluster connector (vehicle harness side) as listed below.
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Diagnosis code Terminal subject to voltage measurement DTC code Diagnosis monitor code Positive Negative P121168 2, 6, 11ECU case GND P121468 3, 7, 10ECU case GND
Standard value: 1 V or less
NO
Faulty harness (short-circuit)YES
Faulty harness in the head cover (short-circuit)
Detail
- Set the starter key to the "LOCK" position and measure resistance between the ECU case GND and a terminal of the signal check harness as listed below.
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Diagnosis code Terminal subject to resistance measurement DTC code Diagnosis monitor code Positive Negative P121168 E35, E36, E37ECU case GND P121468 E19, E20, E60ECU case GND
Standard value: ∞ Ω
NO
Go to [4] Measuring resistance between injector terminals.YES
Go to [5] Measuring resistance between terminals.
Detail
- Measure resistance between the ECU case GND and a terminal of the injector cluster connector (vehicle harness side) as listed below.
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Diagnosis code Terminal subject to voltage measurement DTC code Diagnosis monitor code Positive Negative P121168 2, 6, 11ECU case GND P121468 3, 7, 10ECU case GND
Standard value: ∞ Ω
NO
Faulty harness (short-circuit)YES
Faulty harness in the head cover (short-circuit), faulty injector harness (short-circuit), fault in injector insulation
Detail
- Measure resistance between the terminals of the signal check harness as listed below.
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Diagnosis code Terminal subject to resistance measurement DTC code Diagnosis monitor code P121168 E15 ↔ E35
E16 ↔ E36
E17 ↔ E37
E35 ↔ E36
E36 ↔ E37
E35 ↔ E37
P121468
E39 ↔ E19
E80 ↔ E60
E20 ↔ E40
E19 ↔ E60
E20 ↔ E60
E19 ↔ E20
Standard value: ∞ Ω
NO
Faulty harness (short-circuit)YES
Proceed to [6] Checking of diagnosis code
Detail
- Connect the signal check harness connectors to the ECU and start the engine.
- Use the HINO-DX to delete past malfunctions and then check a present malfunction.
- Replace the engine ECU if the same code is output again. If a normal code is output, there may have been some short-lived abnormalities.
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Detail
- Confirm the DTC P1211 is inactive
- Start the engine and let it idling condition.
- Verify the DTC P1211 is inactive.
- DTC Clear
- Clear the DTC with Hino DX
- Confirm the same DTC is not reoccurred
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- P1211 is reoccur: Return to first process
- Other DTC appear: Refer to concerned Trouble shooting
Complete