Engine Coolant Temperature (ECT)
Switch
ECT SWITCH INSPECTION
1. REMOVE ENGINE UNDER COVER
2. DRAIN ENGINE COOLANT
3. REMOVE ECT SWITCH
(a) Disconnect the ECT switch connector.
(b) Remove the ECT switch.
(c) Remove the O±ring from the ECT switch.
4. INSPECT ECT SWITCH
(a) Usin g an oh mme te r, ch e ck th a t th e re is no co n tin u ity
between the terminals when the coolant temperature is
above 97°C (207°F).
(b) Using an ohmmeter, check that there is continuity between
the terminals when the coolant temperature is below 88°C
(190°F).
If continuity is not as specified, replace the switch.
5. REINSTALL ECT SWITCH
(a) Install a new O±ring to the ECT switch.
(b) Apply soapy water to the O±ring.
(c) Install the ECT switch.
Torque: 7.4 NVm (75 kgfVcm, 65 in.Vlbf)
(d) Connect the ECT switch connector.
6. REFILL WITH ENGINE COOLANT
7. START ENGINE AND CHECK FOR LEAKS
8. REINSTALL ENGINE UNDER COVER
No.1 Radiator Fan Relay
(ºRADIATOR FAN RELAYº)
RADIATOR FAN RELAY INSPECTION
1. w/ Auto Spoiler:
REMOVE LH HEADLIGHT
2. w/o Auto Spoiler:
REMOVE ENGINE UNDER COVER
3. REMOVE RADIATOR FAN RELAY
4. INSPECT RADIATOR FAN RELAY
A. Inspect relay continuity
(a) Using an ohmmeter, check that there is continuity between
terminals 3 and 4.
(b) Check that there is no continuity between terminals 1 and 2.
If continuity is as specified, replace the relay. EG±356
± ENGINECOOLING SYSTEM
229
5. AIR CONDITIONING OPERATION
THE A/C AMPLIFIER RECEIVES VARIOUS SIGNALS, I.E., THE ENGINE RPM FROM THE IGNITER, OUTLET TEMPERATURE SIGNAL
FROM THE A/C THERMISTOR, COOLANT TEMPERATURE FROM THE ENGINE COOLANT TEMP. SENSOR (EFI WATER TEMP. SENSOR)
AND THE LOCK SIGNAL FROM THE A/C COMPRESSOR, ETC.
WHEN THE ENGINE IS STARTED AND THE A/C SW (HEATER CONTROL SW) IS ON, A SIGNAL IS INPUT TO THE A/C AMPLIFIER. AS A
RESULT, THE GROUND CIRCUIT IN A/C AMPLIFIER IS CLOSED AND CURRENT FLOWS FROM HTR FUSE TO TERMINAL 1 OF A/C
MAGNETIC CLUTCH RELAY " TERMINAL 2 " TERMINAL ACMG OF ENGINE CONTROL MODULE (ENGINE ECU) " TERMINAL A/C "
TERMINAL MGC OF A/C AMPLIFIER " TERMINAL GND " GROUND, TURNING THE RELAY ON, SO THAT THE A/C MAGNETIC CLUTCH
IS ON AND THE A/C AMPLIFIER OPERATES.
AT THE SAME TIME, THE ENGINE CONTROL MODULE (ENGINE ECU) DETECTS THE MAGNETIC CLUTCH IS ON AND THE A/C
AMPLIFIER IS OPERATING AND OPENS DIRECTION TO AVOID LOWERING THE ENGINE RPM DURING A/C OPERATING.
WHEN ANY OF THE FOLLOWING SIGNALS ARE INPUT TO THE A/C AMPLIFIER, THE A/C AMPLIFIER OPERATES TO TURN OFF THE
AIR CONDITIONING.
*ENGINE RPM SIGNAL IS HIGH.
*COOLANT TEMP. SIGNAL IS HIGH.
*A SIGNAL THAT THE TEMPERATURE AT THE AIR OUTLET IS LOW.
*A SIGNAL THAT THERE IS A LARGE DIFFERENCE BETWEEN ENGINE SPEED AND COMPRESSOR SPEED.
*A SIGNAL THAT THE REFRIGERANT PRESSURE IS ABNORMALLY HIGH OR LOW.
