Mitsubishi 1989-1993 GALANT Service Manual page 1012

ACTIVE-ELECTRONIC CONTROL SUSPENSION - Troubleshooting
Operation
The left rear and right rear valves are for switching
the air supply and exhaust for the left rear and right
rear shock absorber air springs. These valves are
Diagnostic
If there is damage or disconnection of the heavy-line
circuit, or a malfunction of an output transistor
within the ECU, the alarm light illuminates, and
Diagnostic No. Attitude control
53 Control stop
Actuator compulsory activation
The left rear and right rear valves are activated by
the following.
Code No. Applicable operation
I
Rolling control (left turning, left valve)/rolling
0 9 . 1 0
control (right turning: right valve)
ECU terminal voltages (when connector is connected)
Terminal
Signal
No.
29 Left rear valve activation
signal
27 Right rear valve activation
signal
Checking the left rear/right rear valves activation circuit (with the connector disconnected)
Terminal Connection destination or Measurement
No. measured part
29 Left rear valve
Right rear valve
27
Troubleshooting hints (mechanical malfunctions)
Malfunction
Malfunction probable cause
mode
Stuck in the Air cannot be discharged because
OFF (closed) the valve is stuck in the OFF (closed)
position
due to corrosion, freezing, etc.
caused by moisture penetration.
Stuck in the Air cannot be taken in because the
ON (open) valve is stuck in the ON (open) due
position to corrosion, freezing, etc caused
by moisture penetration.
Valve seat is worn.
at valve seat
Air leakage tc Wear, etc. of the O-ring, etc.
atmosphere
usually, and during air supply, OFF (closed), and are
ON (open) during exhaust.
control is as described in the table below.
Note that the malfunction-detection circuit is the
same for the left rear and right rear valves.
Vehicle-height
Damping force
control
Held at MEDIUM Control stop
I
When the left/right rear valves are ON
During fail-safe (for solenoid valve power source relay switch OFF)
Tester connection
Resistance
Resistance
The left rear and right rear vehicle height
l
increases after rolling control.
The left rear and right rear vehicle height
l
decreases, and the body tilts to one side.
The return pump is activated too frequently
l
When left as is, the rear vehicle-height will decrease.
When left as is, the rear vehicle-height will decrease.
TSB Revision
Switch acceptance
control
HIGH SPORT
Condition
Check condition
Constantly
Constantly
Malfunction
AUTO SOFT
Not accept
Terminal
voltage
o v
o v
Standard
Approx 1011
Approx. 1 Of2
Note
Diagnostic trouble
code No.56 is output
Diagnostic trouble
code No.56 is output
Very slight leakages can-
not be detected. Such
leakage is detected a long
time afterward by a decre-
ase of the vehicle height.