Page 578 of 1500

90-1
GROUP 90
CIRCUIT DIAGRAMS
CONTENTS
HOW TO READ CIRCUIT DIAGRAMS90-3
JUNCTION BLOCK . . . . . . . . . . . . . .90-9
JOINT CONNECTOR . . . . . . . . . . . . .90-11
CENTRALISED JUNCTION . . . . . . . .90-12
POWER DISTRIBUTION SYSTEM . .90-18
STARTING SYSTEM . . . . . . . . . . . . .90-21
IGNITION SYSTEM . . . . . . . . . . . . . .90-22
CHARGING SYSTEM . . . . . . . . . . . .90-23
MULTIPOINT FUEL INJECTION (MPI)
SYSTEM . . . . . . . . . . . . . . . . . . . . . . .90-24
COOLING SYSTEM . . . . . . . . . . . . . .90-29
INVECS-II 5A/T . . . . . . . . . . . . . . . . .90-30
HEADLAMPS . . . . . . . . . . . . . . . . . . .90-35
TAIL LAMP, POSITION LAMP, AND
LICENCE PLATE LAMP . . . . . . . . . .90-38
FOG LAMPS . . . . . . . . . . . . . . . . . . .90-41FRONT DOME LAMP, REAR DOME LAMP,
TRUNK LAMP AND IGNITION KEY HOLE
ILLUMINATION LAMP . . . . . . . . . . . .90-44
GLOVE BOX LAMP . . . . . . . . . . . . . .90-48
VANITY MIRROR LAMP. . . . . . . . . . .90-49
TURN-SIGNAL LAMP AND HAZARD
WARNING LAMP . . . . . . . . . . . . . . . .90-50
BACKUP LAMP . . . . . . . . . . . . . . . . .90-54
STOPLAMP. . . . . . . . . . . . . . . . . . . . .90-55
HORN . . . . . . . . . . . . . . . . . . . . . . . . .90-56
METER AND GAUGE . . . . . . . . . . . . .90-57
BRAKE WARNING LAMP, OIL
PRESSURE WARNING LAMP, FUEL
WARNING LAMP . . . . . . . . . . . . . . . .90-60
POWER WINDOWS . . . . . . . . . . . . . .90-62
CENTRAL DOOR LOCKING
SYSTEM . . . . . . . . . . . . . . . . . . . . . . .90-64
Continued on next page
Page 634 of 1500
METER AND GAUGE
CIRCUIT DIAGRAMS90-57
METER AND GAUGEM1901003501113
Page 635 of 1500
METER AND GAUGE
CIRCUIT DIAGRAMS90-58
Page 636 of 1500
METER AND GAUGE
CIRCUIT DIAGRAMS90-59
METER AND GAUGE (CONTINUED)
Page 789 of 1500

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-88
STEP 21. Check the A/C pressure sensor operation.
(1) Assemble a gauge manifold on the high pressure service
valve.
(2) Disconnect the A/C pressure sensor connector and connect
special tool test harness MB991658 as shown in the
illustration.
(3) Turn ON the engine and then turn ON the air conditioner
switch.
(4) At this time, check to see that the voltage of A/C pressure
sensor terminal No. 2 reflects the specifications of the
figure.
NOTE: The allowance shall be defined as
5%.
Q: Is the A/C pressure sensor operating properly?
YES : Go to Step 22.
NO : Replace the A/C pressure sensor. Check that the air
conditioning works normally.
STEP 22. Check the refrigerant level.
Use the refrigerant recovery station to remove all of the refrig-
erant, and then calculate the amount of the refrigerant and
charge it.
Q: Is the refrigerant level correct?
YES : Go to Step 23.
NO : Correct the refrigerant level (Refer to On-vehicle
Service P.55-144). Check that the air conditioning
works normally.
STEP 23. Replace the A/C-ECU.
Q: Does the A/C operate normally?
YES : The procedure is complete.
NO : Replace the powertrain control module. Check that
the air conditioning works normally.
Page 806 of 1500
AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-105
STEP 2. Using scan tool , check data list item 61: A/C
pressure sensor.
To prevent damage to scan tool , always turn the ignition
switch to the "LOCK" (OFF) position before connecting or
disconnecting scan tool .
(1) Connect scan tool to the data link connector.
(2) Assemble a manifold gauge onto the high pressure service
valve.
(3) Turn ON the engine and then turn ON the air conditioner
switch.
(4) Set scan tool to the data reading mode for item 61: A/C
pressure sensor.
Check that the refrigerant pressure matches the dis-
played value on the scan tool.
(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor within the specified range?
YES : Go to Step 7.
NO : Go to Step 3.
Page 808 of 1500
AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-107
STEP 4. Check the A/C pressure sensor.
(1) Assemble a gauge manifold on the high pressure service
valve.
(2) Disconnect the A/C pressure sensor connector and connect
special tool test harness MB991658 as shown in the
illustration.
(3) Turn ON the engine and then turn ON the air conditioner
switch.
(4) At this time, check to see that the voltage of A/C pressure
sensor terminal No. 2 reflects the specifications of the
figure.
NOTE: The allowance shall be defined as
5%.
Q: Is the A/C pressure sensor in good condition?
YES : Go to Step 5.
NO : Replace the A/C pressure sensor. Check that the air
conditioning works normally.
Page 842 of 1500

ON-VEHICLE SERVICE
HEATER, AIR CONDITIONING AND VENTILATION55-141
ON-VEHICLE SERVICE
REFRIGERANT LEVEL TESTM1552008400408
Use the refrigerant recovery station to remove all of the refrig-
erant, and then calculate the amount of the refrigerant and
charge it.
A/C COMPRESSOR CLUTCH TESTM1552019900032
1. Disconnect the air conditioning compressor clutch connector
to the air conditioning compressor clutch.
2. Connect positive battery voltage directly to the connector for
the air conditioning compressor clutch.
3. If the air conditioning compressor clutch is normal, there will
be a "click." If the pulley and armature do not make contact
("no click"), there is a malfunction.
SIMPLE INSPECTION OF THE A/C PRESSURE
SENSOR
M1552014700118
1. Assemble a gauge manifold on the high pressure service
valve.
2. Disconnect the A/C pressure sensor connector and connect
special tool test harness MB991658 as shown in the illustra-
tion.
3. Turn ON the engine and then turn ON the air conditioner
switch.