AC Compressor control valve LEXUS LS430 2003 Factory Repair Manual

a. The suspension control ECU operates the compressor & motor with the dryer and uses the solenoid
valves to control the vehicle height by analyzing the information based on the switches, sensors and
input signals.
b. Through the 4 height control sensors, the suspension control ECU detects the changes in the vehicle
height that results from the number of occupants or the amount of the load. Then, the suspension
control ECU controls the height control solenoid valves and the compressor & motor with the dryer
in order to automatically adjust the vehicle height to a constant (normal) level.
c. Furthermore, two vehicle heights can be selected by operating the height control switch: HI and
Normal.
d. In cases such as when the vehicle is jacked up, the auto leveling function is prohibited by turning
the ignition switch off.
If the vehicle is raised with its engine running, connect terminals OPB and CG of the DLC3 so the
vehicle height control is not carried out.
e. The absorber control switch selects the shock absorber damping force (normal or sport).
f. w/ Pre-collision safety system:
The suspension control ECU changes the stiffness of the suspension to the hardest setting by
receiving signals (collision unavoidable) from the cruise control ECU.
Function of Components

RC (A20-6) -
GND (A20-4)Y-R - W-BAIR SUS relay
Engine idling, height control switch
from "NORM" to "HIGH" during
compressor operation
8 V or more
CANH (A20-7) -
CANL (A20-8)BR - YCAN communication
lineIG switch OFF54 to 67
ohms
SW1 (A20-9) -
GND (A20-4)O - W-BAbsorber control switch
input signalEngine idling, absorber control
switch "NORM" position10 to 14 V
SW1 (A20-9) -
GND (A20-4)O - W-BAbsorber control switch
input signalEngine idling, absorber control
switch "SPORT" position0 to 1.5 V
SIL (A20-13) -
GND (A20-4)W-G - W-
BDiagnosis tester
communication lineIG switch ONPulse
generation
TD (A20-14) -
GND (A20-4)L-B - W-BHeight control is not
operatingIG switch ON10 to 14 V
HSW (A20-15) -
GND (A20-4)LG-B - W-
BHeight control switch
input signalIG switch ON, height control
switch "NORM" position10 to 14 V
HSW (A20-15) -
GND (A20-4)LG-B - W-
BHeight control switch
input signalIG switch ON, height control
switch "HIGH" position0 to 1.5 V
SLFR (A20-16) -
GND (A20-4)G-W - W-
BHeight control solenoid
valve (FR)IG switch ONBelow 1 V
SLFR (A20-16) -
GND (A20-4)G-W - W-
BHeight control solenoid
valve (FR)Engine idling, height control switch
from "NORM" to "HIGH" or
reverse
8 V or more
SLFL (A20-17) -
GND (A20-4)R-W - W-
BHeight control solenoid
valve (FL)IG switch ONBelow 1 V
SLFL (A20-17) -
GND (A20-4)R-W - W-
BHeight control solenoid
valve (FL)Engine idling, height control switch
from "NORM" to "HIGH" or
reverse
8 V or more
SBL1 (A20-18) -
GND (A20-4)LG-R - W-
BHeight control sensor
power source (FL)IG switch ON4.5 to 5.5 V
VH (A20-19) -
GND (A20-4)P - W-BHeight control indicator
output signalIG switch ON, height control
switch "HIGH"0 to 1.5 V
SBR1 (A20-20) -
GND (A20-4)V-R - W-BHeight control indicator
output signalIG switch ON, height control
switch "NORM"10 to 14 V
SBR1 (A20-20) -
GND (A20-4)V-R - W-BHeight control sensor
power source (FR)IG switch ON4.5 to 5.5 V
SGR1 (A20-21) -
GND (A20-4)R-L - W-BHeight control sensor
ground (FR)AlwaysBelow 1
ohms
SGL1 (A20-22) -
GND (A20-4)LG-B - W-
BHeight control sensor
ground (FL)AlwaysBelow 1
ohms
FAR+ (A21-1) -
FAR- (A21-2)O - R-YSuspension control
actuator (FR)IG switch ONBelow 1
ohms
FBR+ (A21-3) -
FBR- (A21-4)R-G - L-GSuspension control
actuator (FR)IG switch ONBelow 1
ohms
FAL+ (A21-5) -
FAL- (A21-14)G-B - G-RSuspension control
actuator (FL)IG switch ONBelow 1
ohms

FBL+ (A21-6) -
FBL- (A21-16)G-W - G-
OSuspension control
actuator (FL)IG switch ONBelow 1
ohms
SLRL (A21-7) -
GND (A20-4)P-L - W-BHeight control solenoid
valve (RL)IG switch ONBelow 1 V
SLRL (A21-7) -
GND (A20-4)P-L - W-BHeight control solenoid
valve (RL)Engine idling, height control switch
from "NORM" to "HIGH" or
reverse
8 V or more
SLRR (A21-8) -
GND (A20-4)P - W-BHeight control solenoid
valve (RR)IG switch ONBelow 1 V
SLRR (A21-8) -
GND (A20-4)P - W-BHeight control solenoid
valve (RR)Engine idling, height control switch
from "NORM" to "HIGH" or
reverse
8 V or more
RM+ (A21-17) -
GND (A20-4)BR-Y - W-
BMotor lock (+)
Engine idling, height control switch
from "NORM" to "HIGH" during
compressor operation
Below 1 V
RM- (A21-18) -
GND (A20-4)BR-B - W-
BMotor lock (-)AlwaysBelow 1
ohms
SHR2 (A21-19) -
GND (A20-4)W - W-BHeight control sensor
(HID rear)IG switch ON0.5 to 4.5 V
SHFR (A21-20) -
GND (A20-4)B-W - W-
BHeight control sensor
(FR)IG switch ON0.5 to 4.5 V
SHFR (A21-20) -
GND (A20-4)B-W - W-
BHeight control sensor
(FR)Engine idling, height control switch
"NORM"Approx. 2.5
V
SHF2 (A21-21) -
GND (A20-4)V-G - W-BHeight control sensor
(HID front)IG switch ON0.5 to 4.5 V
SHFL (A21-22) -
GND (A20-4)L - W-BHeight control sensor
(FL)IG switch ON0.5 to 4.5 V
SHFL (A21-22) -
GND (A20-4)L - W-BHeight control sensor
(FL)Engine idling, height control switch
"NORM"Approx. 2.5
V
SBL3 (A21-23) -
GND (A20-4)B - W-BHeight control sensor
power source (HID)IG switch ON4.5 to 5.5 V
SGL3 (A21-24) -
GND (A20-4)V-Y - W-BHeight control sensor
ground (HID)AlwaysBelow 1
ohms
RAR+ (A22-2) -
RAR- (A22-3)Y - SBSuspension control
actuator (RR)IG switch ONBelow 1
ohms
RBR+ (A22-4) -
RBR- (A22-5)LG - PSuspension control
actuator (RR)IG switch ONBelow 1
ohms
RAL+ (A22-6) -
RAL- (A22-7)L - GSuspension control
actuator (RL)IG switch ONBelow 1
ohms
RBL+ (A22-8) -
RBL- (A22-9)O - BRSuspension control
actuator (RLIG switch ONBelow 1
ohms
SGR3 (A22-12) -
GND (A20-4)W - W-BAcceleration sensor
ground (rear)AlwaysBelow 1
ohms
SBR3 (A22-15) -
GND (A20-4)R - W-BAcceleration sensor
power source (rear)IG switch ON4.5 to 5.5 V

For details of each code, go to Fig. 16
DTC C1715, DTC C1716, DTC C1717,
DTC C1791, DTC C1792, DTC C1793
RIGHT FRONT ACCELERATION SENSOR CIRCUIT
DTC C1725, DTC C1726, DTC C1727,
DTC C1728
RIGHT FRONT ABSORBER CONTROL ACTUATOR
CIRCUIT
DTC C1735EXHAUST SOLENOID VALVE CIRCUIT
DTC C1737, DTC C1738, DTC C1739,
DTC C1740
RIGHT FRONT HEIGHT CONTROL SOLENOID
VALVE CIRCUIT
DTC C1741AIR SUS RELAY CIRCUIT
DTC C1742HEIGHT CONTROL COMPRESSOR CIRCUIT
DTC C1751, DTC C1752CONTINUOUS ELECTRIC CURRENT TO HEIGHT
CONTROL COMPRESSOR
DTC C1761ECU MALFUNCTION
DTC C1774POWER SOURCE CIRCUIT
DTC C1776SPEED SENSOR CIRCUIT
DTC C1777STEERING ANGLE SENSOR CIRCUIT
DTC C1786HEIGHT CONTROL SWITCH CIRCUIT (TEST
DIAGNOSIS)
DTC C1787ABSORBER CONTROL SWITCH CIRCUIT (TEST
DIAGNOSIS)

OK:Go to next step
2.INSPECT EXHAUST SOLENOID VALVE
a. Disconnect the exhaust solenoid valve connector.
b. Measure the resistance according to the value (s) in the table below.
TESTER CONNECTION STANDARD SPECIFIED CONDITION
c. Connect terminal 1 (SLEX) to the battery positive (+) terminal, and terminal 2 (GND) to the battery
negative (-) terminal.
d. Check the operating sound of the exhaust solenoid valve.
OK:
It should make an operating sound (click).
HINT:
When a malfunction is found in the exhaust solenoid valve, replace the height control compressor assy.
NG: REPLACE HEIGHT CONTROL COMPRESSOR ASSY (SEE REPLACEMENT
)
OK:Go to next step
Tester ConnectionSpecified Condition
1 (SLEX) - 2 (GND)10 to 14 ohms

c. Check the operating sound of the exhaust solenoid valve.
OK:
It should make an operating sound (click).
HINT:
When a malfunction is found in the exhaust solenoid valve, replace the height control compressor assy.
NG: REPLACE HEIGHT CONTROL COMPRESSOR ASSY (SEE REPLACEMENT
)
OK:Go to next step
Fig. 103: Identifying Exhaust Solenoid Valve Connector Terminals

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

c. Check the operating sound of the exhaust solenoid valve.
OK:
It should make an operating sound (click).
HINT:
When a malfunction is found in the exhaust solenoid valve, replace the height control compressor assy.
NG: REPLACE HEIGHT CONTROL COMPRESSOR ASSY (SEE REPLACEMENT
)
OK:Go to next step
6.INSPECT HEIGHT CONTROL SENSOR LINK SUB-ASSY
a. Inspect and adjust the height control sensor link sub-assy (see ON
-VEHICLE INSPECTION ).
NG: REPLACE HEIGHT CONTROL SENSOR LINK SUB-ASSY
OK: CHECK AND REPAIR OR REPLACE PARTS
Air tube is clogged (see ON-VEHICLE INSPECTION ).
Compressor is faulty (see REPLACEMENT ).
Height control sensor sub-assy is faulty (see REPLACEMENT - HEIGHT CONTROL
SENSOR SUB-ASSY FRONT , REPLACEMENT - HEIGHT CONTROL SENSOR SUB-
ASSY REAR LH ).
Foreign material in the height control solenoid valve and/or exhaust solenoid valve (see
REPLACEMENT
- HEIGHT CONTROL COMPRESSOR ASSY , REPLACEMENT -
HEIGHT CONTROL VALVE SUB
-ASSY NO.1 , REPLACEMENT - HEIGHT CONTROL
VALVE SUB-ASSY NO.2 ).
Suspension control ECU malfunction (see REPLACEMENT ).
CIRCUIT DESCRIPTION

ENGINE IMMOBILIZER DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION (W/SMART
KEY)
ENGINE IMMOBILIZER DIAGNOSTIC TROUBLE CODES (DTC) IDENTIFICATION (W/O
SMART KEY)
C1714, DTC C1714 CIRCUIT
DTC C1715, DTC C1716, DTC C1717, DTC
C1791, DTC C1792, DTC C1793
RIGHT FRONT ACCELERATION SENSOR CIRCUIT
DTC C1725, DTC C1726, DTC C1727, DTC
C1728
RIGHT FRONT ABSORBER CONTROL ACTUATOR
CIRCUIT
DTC C1735 EXHAUST SOLENOID VALVE CIRCUIT
DTC C1737, DTC C1738, DTC C1739, DTC
C1740
RIGHT FRONT HEIGHT CONTROL SOLENOID
VALVE CIRCUIT
DTC C1741 AIR SUS RELAY CIRCUIT
DTC C1742 HEIGHT CONTROL COMPRESSOR CIRCUIT
DTC C1751, DTC C1752 CONTINUOUS ELECTRIC CURRENT TO HEIGHT
CONTROL COMPRESSOR
DTC C1761 ECU MALFUNCTION
DTC C1774 POWER SOURCE CIRCUIT
DTC C1776 SPEED SENSOR CIRCUIT
DTC C1777 STEERING ANGLE SENSOR CIRCUIT
DTC C1786 HEIGHT CONTROL SWITCH CIRCUIT (TEST
DIAGNOSIS)
DTC C1787 ABSORBER CONTROL SWITCH CIRCUIT (TEST
DIAGNOSIS)
DTCDescription
DTC B2780 PUSH SWITCH/KEY UNLOCK WARNING
SWITCH MALFUNCTION
DTC B2793 TRANSPONDER CHIP MALFUNCTION
DTC B2794 UNMATCHED ENCRYPTION CODE
DTC B2795 UNMATCHED KEY CODE
DTC B2797 COMMUNICATION MALFUNCTION NO.1
DTC B2799 ENGINE IMMOBILIZER SYSTEM
MALFUNCTION
DTCDescription
DTC B2780 PUSH SWITCH/KEY UNLOCK WARNING
SWITCH MALFUNCTION
DTC B2793 TRANSPONDER CHIP MALFUNCTION