1996 TOYOTA RAV4 air conditioning

65
2. CONTROL SYSTEM
*SFI
THE SFI SYSTEM MONITORS THE ENGINE CONDITION THROUGH THE SIGNALS, WHICH ARE INPUT FROM EACH SENSOR (INPUT
SIGNALS (1) TO (11)). THE BEST FUEL INJECTION VOLUME IS DECIDED BASED ON THIS DATA AND THE PROGRAM MEMORIZED
BY THE ENGINE CONTROL MODULE, AND THE CONTROL SIGNAL IS OUTPUT TO TERMINALS #10, #20, #30, AND #40 OF THE
ENGINE CONTROL MODULE TO OPERATE THE INJECTOR (INJECT THE FUEL). THE SFI SYSTEM PRODUCES CONTROL OF FUEL
INJECTION OPERATION BY THE ENGINE CONTROL MODULE IN RESPONSE TO THE DRIVING CONDITIONS.
*IDLE SPEED CONTROL SYSTEM
THE IDLE SPEED CONTROL SYSTEM INCREASES THE RPM AND PROVIDES IDLING STABILITY FOR FAST IDLE-UP WHEN THE
ENGINE IS COLD AND WHEN THE IDLE SPEED HAS DROPPED DUE TO ELECTRICAL LOAD, ETC. THE ENGINE CONTROL MODULE
EVALUATES THE SIGNALS FROM EACH SENSOR (INPUT SIGNALS (1 TO 5, 11), OUTPUTS CURRENT TO TERMINAL ISCO AND ISCC,
AND CONTROLS THE IDLE AIR CONTROL VALVE.
*A/C CUT CONTROL SYSTEM
WHEN THE VEHICLE SUDDENLY ACCELERATES FROM LOW ENGINE SPEED, THIS SYSTEM CUTS OFF AIR CONDITIONING
OPERATION FOR A FIXED PERIOD OF TIME IN RESPONSE TO THE SPEED SENSOR, THROTTLE VALVE OPENING ANGLE AND
INTAKE MANIFOLD PRESSURE IN ORDER TO MAINTAIN ACCELERATION PERFORMANCE.
THE ENGINE CONTROL MODULE RECEIVES INPUT SIGNALS (4, 5 AND 9), AND INPUTS SIGNALS TO TERMINAL ACT.
3. DIAGNOSIS SYSTEM
WITH THE DIAGNOSIS SYSTEM, WHEN THERE IS A MALFUNCTION IN THE ENGINE CONTROL MODULE SIGNAL SYSTEM, THE
MALFUNCTIONING SYSTEM IS RECORDED IN THE MEMORY. THE MALFUNCTIONING SYSTEM CAN THEN BE FOUND BY READING
THE DISPLAY (CODE) OF THE MALFUNCTION INDICATOR LAMP.
4. FAIL-SAFE SYSTEM
WHEN A MALFUNCTION OCCURS ON ANY SYSTEM, IF THERE IS A POSSIBILITY OF ENGINE THROUBLE BEING CAUSED BY
CONTINUED CONTROL BASED IN THE SIGNALS FROM THAT SYSTEM, THE FAIL-SAFE SYSTEM EITHER CONTROLS THE SYSTEM BY
USING DATA (STANDARD VALUES) RECORDED IN THE ENGINE CONTROL MODULE MEMORY OR ELSE STOPS THE ENGINE.

71
E 4 (A), E 5 (B), E 6 (C) ENGINE CONTROL MODULE
BATT -E1 : ALWAYS 9.0-14.0 VOLTS
+B -E1 :9.0-14.0 VOLTS (IGNITION SW AT ON POSITION)
VC -E2 :4-5-5.5 VOLTS (IGNITION SW AT ON POSITION)
VTA -E2 :0.3-0.8 VOLTS (IGNITION SW ON AND THROTTLE VALVE FULLY CLOSED)
:3.2-4.9 VOLTS (IGNITION SW ON AND THROTTLE VALVE OPEN)
PIM -E2 :3.3-3.9 VOLTS (IGNITION SW AT ON POSITION)
#10,#20, #30, #40-E01, E02 : 9.0-14.0 VOLTS (IGNITION SW AT ON POSITION)
THA -E2 :0.5-3.4 VOLTS (IGNITION SW ON AND THE INTAKE AIR TEMP 20
C, 68
F)
THW -E2 :0.2-1.0 VOLTS (IGNITION SW ON AND THE COOLANT TEMP 80
C, 176
F)
STA -E1 :6.0-14.0 VOLTS (ENGINE CRANKING)
IGT -E1 :0.8-1.2 VOLTS (ENGINE CRANKING OR IDLING)
W -E1 :9.0-14.0 VOLTS (NO TROUBLE AND ENGINE RUNNING)
ACT -E1 :4.5-5.5 VOLTS (IGNITION SW ON AND AIR CONDITIONING ON)
AC1 -E1 :0-3.0 VOLTS (IGNITION SW ON AND AIR CONDITIONING ON)
ISCO, ISCC-E1 :9.0-14.0 VOLTS (IGNITION SW AT ON POSITION)
TE1 -E1 :9.0-14.0 VOLTS (IGNITION SW ON AND DATA LINK CONNECTOR 1 TE1-E1 NOT CONNECTED)
:0-3.0 VOLTS (IGNITION SW ON AND DATA LINK CONNECTOR 1 TE1-E1 CONNECTED)
NSW -E1 :0-3.0 VOLTS (IGNITION SW ON AND PARK/NEUTRAL POSITION SW P OR N RANGE)
:9.0-14.0 VOLTS (IGNITION SW ON AND PARK/NEUTRAL POSITION SW EXCEPT POSITION P AND N RANGE)
RESISTANCE OF ENGINE CONTROL MODULE WIRING CONNECTOR
(DISCONNECT WIRING CONNECTOR)
VTA -E2 :3.3-10.0 KW (THROTTLE VALVE FULLY OPEN)
:0.2-0.8 KW (THROTTLE VALVE FULLY CLOSED)
VC -E2 :3.0-7.0 KW
THA -E2 :2.0-3.0 KW (INTAKE AIR TEMP 20
C, 68
F)
THW -E2 :0.2-0.4 KW (COOLANT TEMP 80
C, 176
F)
G+ -G- :0.17-0.21 KW
ISCO, ISCC-+B :19.3-22.3 W
(5) CIRCUIT OPENING RELAY
(5) 3 -(5) 5 : CLOSED WITH THE IGNITION SW ON OR ST POSITION
(6) EFI MAIN RELAY
(6) 3-(6) 5 : CLOSED WITH THE IGNITION SW ON OR ST POSITION
E 2 ENGINE COOLANT TEMP. SENSOR
1-2 :14.6-17.8 KW (-20
C, -4
F)
5.88 KW (0
C, 32
F)
2.21-2.69 KW (20
C, 68
F)
1.14 KW (40
C, 104
F)
0.584 KW (60
C, 140
F)
0.29-0.354 KW (80
C, 176
F)
I 5, I 6, I 7, I 8 INJECTOR
1-2 : APPROX. 13.8 W
T 1 THROTTLE POSITION SENSOR
3-1 :0.2-5.7 KW WITH CLEARANCE BETWEEN LEVER AND THE STOP SCREW 0 MM (0 IN.)
3-1 :2.0-10.2 KW WITH THROTTLE VALVE FULLY OPEN
2-1 : LESS THAN 2.3 KW WITH CLEARANCE BETWEEN THE LEVER AND THE STOP SCREW 0.5 MM (0.02 IN.)
WITH CLEARANCE BETWEEN LEVER AND THE STOP SCREW 0.7 MM (0.028 IN.)
SERVICE HINTS

160
AIR CONDITIONING
IH 1 1
IG IB210
W-BB-L B-L
B-L
B-L
B-L B B B-W
B-W B-W
R-B
BR
OO
W-B
W-B
W-B W-B
W-B
FROM POW ER SOURCE SYSTEM (
SEE PAGE 54)
IBLE
K BLOCK
B-L
I 8
B-L
GAUGE
E BLOCK]
-L R-L
L-R50A H TR5FUS
LIN F 7 3
B BA C
JUN CTIO N
CONNECTORB J10 , J11A
R-L
IH 1 22 1
1324
B-W
BLOW ER RESISTORBLOWER MOTORB 4B 3
821
5
6 HI M2 M1
LO BLO WER S W B 5
OFF
10A
[FUS
4F 8
1B 81E 8
R
M
4C 84C1 4B 44C 7 4B 8
34 15
2 4B 74A2
4B 14B5127. 5A A/C HEATER
RELAY4B 9

162
AIR CONDITIONING
HEATER BLOWER MOTOR OPERATION
CURRENT IS APPLIED AT ALL TIMES THROUGH THE HTR FUSE TO TERMINAL 5 OF THE HEATER RELAY.
WHEN THE IGNITION SW IS TURNED ON, CURRENT FLOWS THROUGH THE GAUGE FUSE TO TERMINAL 1 OF THE HEATER RELAY
"THE COIL "TERMINAL 3 "TERMINAL 5 OF THE BLOWER SW.
*LOW SPEED OPERATION
WHEN THE BLOWER SW IS MOVED TO LO POSITION, THE CURRENT FLOWS TO TERMINAL 5 OF THE BLOWER SW "TERMINAL 6
"GROUND, CAUSING THE HEATER RELAY TO SWITCH ON. THIS CAUSES THE CURRENT TO FLOW FROM THE HTR FUSE "
TERMINAL 5 OF THE HEATER RELAY "TERMINAL 4 "TERMINAL 1 OF THE BLOWER MOTOR "TERMINAL 2 "TERMINAL 1 OF
THE BLOWER RESISTOR "TERMINAL 4 "GROUND, CAUSING THE BLOWER MOTOR TO ROTATE AT LOW SPEED.
*MEDIUM SPEED OPERATION (OPERATION AT M1, M2)
WHEN THE BLOWER SW IS MOVED TO M1 POSITION, THE CURRENT FLOWING TO TERMINAL 5 OF THE BLOWER SW "
TERMINAL 6 "GROUND, TURNS THE HEATER RELAY ON. THIS CAUSES THE CURRENT TO FLOW FROM THE HTR FUSE "
TERMINAL 5 OF THE HEATER RELAY "TERMINAL 4 "TERMINAL 1 OF THE BLOWER MOTOR "TERMINAL 2 "TERMINAL 1 OF
THE BLOWER RESISTOR "TERMINAL 2 "TERMINAL 1 OF THE BLOWER SW "TERMINAL 6 "GROUND. THIS TIME, THE
BLOWER RESISTANCE OF THE BLOWER RESISTOR IS LESS THAN AT LOW SPEED, SO THE BLOWER MOTOR ROTATES AT
MEDIUM LOW SPEED.
WHEN THE BLOWER SW IS MOVED TO M2 POSITION, CURRENT FLOWING THROUGH THE MOTOR FLOWS FROM TERMINAL 1 OF
THE BLOWER RESISTOR "TERMINAL 3 "TERMINAL 2 OF THE BLOWER SW "TERMINAL 6 "GROUND. THIS TIME,
RESISTANCE OF THE BLOWER RESISTOR IS LESS THAN AT M1 POSITION, SO THE BLOWER MOTOR ROTATES AT MEDIUM HIGH
SPEED.
*HIGH SPEED OPERATION
WHEN THE BLOWER SW IS MOVED TO HI POSITION, THE CURRENT FLOWS TO TERMINAL 5 OF THE BLOWER SW "TERMINAL 6
"GROUND AND TURNS THE HEATER RELAY ON.
THIS CAUSES THE CURRENT TO FLOW FROM THE HTR FUSE TO TERMINAL 5 OF THE HEATER RELAY "TERMINAL 4 "
TERMINAL 1 OF THE BLOWER MOTOR "TERMINAL 2 "TERMINAL 8 OF THE BLOWER SW "TERMINAL 6 "GROUND, CAUSING
THE BLOWER MOTOR TO ROTATE AT HIGH SPEED.
A 3 A/C DUAL PRESSURE SW
1-4 : OPEN WITH THE PRESSURE LESS THAN 2.0 KG/CM2 (30 PSI, 206 KPA) OR ABOVE 32 KG/CM2 (384 PSI, 2648 KPA)A12 A/C AMPLIFIER
12-5 : CONTINUITY WITH THE A/C CONTROL SW ON AND THE IGNITION SW AT ON POSITION
13-GROUND : ALWAYS CONTINUITY
05-GROUND : ALWAYS CONTINUITY
02-GROUND : APPROX. 12 VOLTS WITH THE IGNITION SW ON
A14 A/C THERMISTOR
1-2 : APPROX. 2341
234 W AT 15
C (59
F)
B 4 BLOWER RESISTOR
1-3 : APPROX. 0.4 W
1-2 : APPROX. 1.1 W
1-4 : APPROX. 2.8 W
B 5 BLOWER SW
5-6 : CONTINUITY WITH THE BLOWER SW AT LO, M1, M2 OR HI POSITION
1-6 : CONTINUITY WITH THE BLOWER SW AT M1 POSITION
2-6 : CONTINUITY WITH THE BLOWER SW AT M2 POSITION
8-6 : CONTINUITY WITH THE BLOWER SW AT HI POSITION
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
A 228B 430I 229
A 328B 530J 331
A1230D 330J 431
A1330E 631J10A31
A1430F 728J11B31
B 330F 831
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
625R/B NO. 6 (ENGINE COMPARTMENT LEFT)
SYSTEM OUTLINE
SERVICE HINTS

K OVERALL ELECTRICAL WIRING DIAGRAM
1
234
20 RAV4
1 AC C
IG 1
IG 2
ST2 AM1
2
AM2
1D 9
1K 4
21D 7
1E 81F 1
1B 84B 74A2
22 1
M 4B 5 4B 1
2IH1 1IH12 1
5 3 66
66
6 EA1
3 IB210
3IG2
11 IB2 4C 7 4C 1 4C 8 4B 8
4
4 87 10 13 14 9 12 2 5 1 2 8
6
IG 2 3 1
1 2 1
4
5 HI M2 M1 LO64 5
15
6
1 I1 0
IG N ITION S W
F 8
10A
GAUGE
[FU S E
BLOCK]
BBB-WB-WB- W
W W R-L L-R
BR-LR-LR-L O
L-R L- B B-R B-R Y
W-RR-Y Y-GB
Y
G-W
L BR BR W-R
L-B
W-BL-Y
L-B
OW-B W-B
W-B W-B
R-B
BR
W
B-L
R-W B-L
B-L
B 4
BLOWER RESISTOR
Power Source Air Conditioning
R ight kick panel 34 B-Y
7. 5A A/C
B 3
BLOWER MOTORB-L
A 3
A/C DUAL PRESSURE SW
L- Y
F 7
FUSIBLE
LINK BLOCK
BATTERY
50A HTR 100A ALT
B 5
BLO W ER SWA13
A/C CONTROL
SW
2 1
A 2
A/C MAGNETIC CLUTCH
AND LOCK SENSOR
A14
A/C THERMISTOR
IG- E IG+ MGC TE SSR- SSR+ LED+ A/C ACT AC1
A12
A/C AMPLIFIER
To E ngine C ontrol
M odule< 2- 2 F rom Ign iter< 5- 4
B-L MG/C RELAY ON
OFF
HEATER
RELAY
40A
AM1
521
43
2 24
G-W
B- L
To FAN NO. 3
Relay< 19-4 B-L
4IG2
12 IB2
BR F rom E ngine C ontrol
Module<2-2
B-L 4B 94B4
BR
A
A
A
J 3
JUNCTION
CONNECTOR
B- L
B-L
1 2B- L
Y D 3
D EFR OSTER
MODE SW
W-B
CA
BB J10 A , J11 B
JU NC TION
CONNECTOR
AAAAAA
BBBCCC JUNCTION CONNECTOR
B J11 G R A YA J10 G R A Y
OFF