SC–62 SUSPENSION CONTROL – ACTIVE HEIGHT CONTROL SUSPENSION

DTC C1761/61 ECU Malfunction

DESCRIPTION
HINT:
"ECU" refers to the suspension control ECU.
DTC No. DTC Detection Condition Trouble Area
C1761/61 When the EEPROM of the ECU has become • ECU internal memory error
abnormal • Suspension control ECU

1 CLEAR DTC

NEXT

2 CHECK FOR DTC

(a) Recheck for DTC (see page SC-16).

OK:
C1767/67 is not output.
NG REPLACE SUSPENSION CONTROL ECU

OK

NO PROBLEM

SC
 SUSPENSION CONTROL – ACTIVE HEIGHT CONTROL SUSPENSION SC–63

DTC C1762/62 Abnormal Oil Pressure for Pump

DESCRIPTION
DTC No. DTC Detection Condition Trouble Area
C1762/62 Either of the following 1. or 2. is detected: • AHC pump and motor
1. While the motor relay is in operation, the • Fluid pressure sensor
condition that the fluid pressure is less • AHC motor relay
than 0.5 MPa continued for 0.6 sec. • Fluid empty
2. When the pump motor is in delivering • Suspension control ECU
condition, the delivery portion does not • Wire harness
change and the fluid pressure change is
small.

Fail-safe function:
If the DTC C1762/62 is detected, the height control is prohibited after adjusting the vehicle height to the
standard height case than the height is higher than the standard or to the lowest wheel of the 4 wheels in
case that the height is lower than the standard.

1 CHECK FLUID LEVEL OF RESERVOIR TANK

(a) Refer to "Check Fluid Level of the Reservoir Tank"

procedure (see page SP-2).
NG FILL THE RESERVOIR TANK WITH
SUSPENSION FLUID AHC

OK

2 CHECK OPERATION OF AHC PUMP AND MOTOR

(a) Disconnect the AHC pump and motor connector.

(b) Connect positive (+) lead to terminal 2 and negative (-)
lead to terminal 1 of the AHC pump and motor connector,
check that the AHC pump motor operated.

2 1 NG REPLACE AHC PUMP AND MOTOR

(+) (-)

H100750E01

OK
SC
 SC–64 SUSPENSION CONTROL – ACTIVE HEIGHT CONTROL SUSPENSION

3 BLEED AIR OF AHC AND AVS HYDRAULIC SYSTEM

(a) Using SST, connect terminals 12 (TS) and 4 (CG) of the

DLC3.
SST 09843-18040
CG
(b) Push the DOWN button of the height select switch 5
times or more within 5 seconds after starting the engine.
HINT:
At this time, the height control OFF indicator light flashes
at 0.25 second intervals.
(c) Change the damping mode select switch to the
COMFORT position.
TS DLC3
(d) Push and hold the UP button of the height select switch
for 10 seconds.
HINT:
At this time, the AHC motor relay comes ON in order to
raise the vehicle height of the front wheels and air inside
of the AHC and AVS hydraulic system start to bleed with
the pump motor operating.
NOTICE:
Do not raise the vehicle height higher than the HI
position when raising it with the active test.
(e) Turn the ignition switch OFF, and disconnect SST from
DLC3.
SST 09843-18040
COMFORT UP Button

H100807E06

NEXT

SC
 SUSPENSION CONTROL – ACTIVE HEIGHT CONTROL SUSPENSION SC–65

4 INSPECT AHC MOTOR RELAY (Marking: AHC)

(a) Remove the AHC motor relay from the engine room
junction bock.
(b) Measure the resistance between each pair of terminal of
the motor relay.
Standard resistance
Tester Connection Specified Condition
3-4 Reference value 62 Ω
1 1-2 10 kΩ or higher

(c) Apply battery positive voltage between terminals 3 and

2 4.
(d) Measure the resistance between terminals 1 and 2.
4 Standard resistance
Tester Connection Specified Condition
3 1-2 Below 1 Ω

1 NG REPLACE AHC MOTOR RELAY

4
(-)
3
(+)
H100745E02

OK

5 CHECK WIRE HARNESS (FLUID PRESSURE SENSOR - SUSPENSION CONTROL ECU)

NG REPAIR OR REPLACE HARNESS AND

CONNECTOR

OK

6 CHECK FLUID PRESSURE SENSOR

SC
(a) Start the engine and push the vehicle height select
switch to select the "N" mode.
(b) Measure the voltage between terminals 2 and 3 of the
(+) fluid pressure sensor connector.
Standard voltage
Tester Connection Specified Condition
(-)
F1-2 - F1-3 1.48 to 1.85 V
2
3 H100734E01
NG REPLACE FLUID PRESSURE SENSOR
 SC–66 SUSPENSION CONTROL – ACTIVE HEIGHT CONTROL SUSPENSION

OK

REPLACE SUSPENSION CONTROL ECU

SC