Maintenance Manual for J2 Sedan
Electronic Control System
of Engine
209
Fault code: P0117 “the circuit voltage of engine coolant temperature sensor is too low”
S/N
Step
Check result
Subsequent step
1
Connect the diagnosis device and adapter, and turn the ignition switch
to ON position.
Next step
Yes
To Step 6
2
Observe if the “Coolant temperature” in the data flow is equivalent to
the engine temperature (depending on the engine temperature then).
Notice: if the displayed value is always -40
, the circuit may be
℃
open.
No
Next step
Yes
Next step
3
Unplug the connector of coolant temperature sensor on the harness,
and check if the resistance between Pins 1# and 2# of sensor
corresponds to its temperature by the multimeter (refer to the relevant
section in this repair manual for the details).
No
Replace the
sensor
Yes
To Step 6
4
Unplug the connector of coolant temperature sensor on the harness,
and check if the voltage between Pins 1# and 2# of this connector is
about 5v by the multimeter.
No
Next step
Yes
Repair or replace
the harness
5
Check if the circuits connecting Pins 40# and 41# of ECU
respectively to Pins 1# and 2# of sensor connector are open or short
to power source.
No
Next step
Yes
Diagnosis help
6
Start the engine and run the engine idly. Observe the change of the
“Coolant temperature” value on the diagnosis meter, and at this
moment the displayed value shall increase with the rising of engine
coolant.
No
Replace the
sensor
Fault code: P0118 “the circuit voltage of engine coolant temperature sensor is too high”
S/N
Step
Check result
Subsequent step
1
Connect the diagnosis device and adapter, and turn the ignition switch
to ON position.
Next step
Yes
To Step 6
2
Observe if the “Coolant temperature” in the data flow is equivalent to
the engine temperature (depending on the engine temperature then).
Notice: if the displayed value is always -40
, the circuit may be
℃
open.
No
Next step
Yes
Next step
3
Unplug the connector of coolant temperature sensor on the harness,
and check if the resistance between Pins 1# and 2# of sensor
corresponds to its temperature by the multimeter (refer to the relevant
section in this repair manual for the details).
No
Replace the
sensor
Yes
To Step 6
4
Unplug the connector of coolant temperature sensor on the harness,
and check if the voltage between Pins 1# and 2# of this connector is
about 5v by the multimeter.
No
Next step
Yes
Repair or replace
the harness
5
Check if the circuits connecting Pins 40# and 41# of ECU
respectively to Pins 1# and 2# of sensor connector are short to
ground.
No
Next step
Yes
Diagnosis help
6
Start the engine and run the engine idly. Observe the change of the
“Coolant temperature” value on the diagnosis meter, and at this
moment the displayed value shall increase with the rising of engine
coolant.
No
Replace the
sensor
