Service manual

FUEL INJECTION SYSTEM
FI ifl
Fault code No. 21 Symptom Coolant temperature sensor open or short circuit is detected.
Used diagnostic code No. D06 (coolant temperature sensor)
Order
Inspection operation item and
probable cause
Operation item and countermeasure
Reinstatement
method
1
2
3
4
Installed condition of sensor Check the installed area for looseness or
pinching.
Reinstated by turn-
ing the main switch
ON.
1
2
3
4
Connected condition of con-
nector
Inspect the coupler for any
pins that may have pulled
out.
Check the locking condition
of the coupler.
If there is a malfunction, repair it and connect
it securely.
Coolant temperature sensor coupler
Main wiring harness ECU coupler
Reinstated by turn-
ing the main switch
ON.
1
2
3
4
Open or short circuit in wiring
harness.
Repair or replace if there is an open or short
circuit.
Between sensor coupler and ECU coupler
black/blue-black/blue
green/red - green/red
Reinstated by turn-
ing the main switch
ON.
1
2
3
4 Defective coolant temperature
sensor.
Execute the diagnostic mode (code No.D06)
Replace if defective.
Refer to “COOLING SYSTEM” in chapter 8.
Reinstated by turn-
ing the main switch
ON.
7-17