Ecu Temperature Sensor; P0668/4: Failure With Ecu Temperature Sensor (Low Voltage) - Yanmar 3TNV82A Troubleshooting Manual

FAILURE DIAGNOSIS

ECU Temperature Sensor

(1) P0668/4: Failure with ECU Temperature Sensor (Low Voltage)

DTC P0668/4
DTC Detecting Conditions
1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator
1. Key switch ON.
2. Sensor voltage 1.0 [V] (at 140°C) or lower.
3. Four flashes followed by one flash.
Movement at Error occurrence
Error Mode [Operation Continuation]: No obstacles to control the engine.
The engine continues to run with the ECU temperature set to the default of 30[°C].
Run restricted? No.
Recovery Yes: This error will be automatically reset when a normal sensor voltage (1.0 to
Conditions
Remarks
Estimation of Failure cause/Error condition
• The E-ECU internal circuitry may be faulty.
Diagnosis Description
1) Initial diagnosis
with the diagnosis
tool
1-40
DTCs (Diagnostic Trouble Codes) General Description
4.6[V]) is input.
• Check the fault indication.
• Check the ECU temperature.
*For details of the method and the procedure of diagnosis, see P.1-154
Failure with ECU Temperature Sensor (Low Voltage)
E-ECU
TNV DI Service Manual
Check points