
C:\TEMP\ml59101.doc | Revised: 20JUN18 | Page 12 of 39
TROUBLE SHOOTING
PROBLEM
SOLUTION
DIAGRAMS
Step 2b. Cont.
Check for +12 volts between the two pins of the MIOM
Packard connector. If power is present, replace the valve. If
power is not present, the issue is the connection or MIOM. If
the connection of the wires in the connector is ok, replace the
MIOM.
If the bag does not inflate with the manifold T-handle opened,
the issue is the Height control valve or possibly something in
the system plumbing.
Make sure the T-handle is closed
snugly after completing the test.
NOTE:
If the T-handle does not turn fairly easy, do not try to
force it, you can damage the manifold. Go ahead with the
voltage test at the valve and if voltage is ok, remove the travel
valve. If air comes out of the manifold, replace the valve. If no
air comes out, the issue is the Height Control Valve or the
plumbing.
If the travel valve LED is not lit,
turn the ignition off,
unplug
the valve, the main MIOM connector and the 2 pin MIOM plug
for high current and ground. Wait about 10 seconds, then plug
the main connector and the 2 pin connector back in. Do not
plug the valve back in. Turn the ignition on. If the travel valve
LED now comes on, replace that travel valve. If the travel
valve LED still does not come on, replace the MIOM.
W2700
TRAVEL
RS
B
A
A
B
A
B
B
A
B
A
A
B
A
B
TRAVEL
W1700
LS
RED (6100)
WHITE (6234)
6245
2700
1700
6246
WHITE
BLACK
MAIN
CONNECTOR
REFER TO MP84.3181
Step 3.
With the ignition in the “ON” or “ACC” position and the park brake set, push the “DUMP” button to exhaust the air
from all the air bags. The DUMP light should start flashing and continue flashing. When air has stopped exhausting, push
the “CANCEL” button. The DUMP light should stop flashing. Check that all the air bags are totally deflated.
Step 3a. The
DUMP light will
not come on
and flash.
Whenever the ignition is in the “ON” or “ACC” position, there
should be +12 volts on the black 9900 wire going to the main
connector, pin C6, of the front MIOM. This is the speed switch
wire.
If +12 is not present
, there is an issue with the
transmission output, the 9900 wire, its connections to the
HWH MIOM or the transmission speed switch.
If +12 is
present, replace the touch panel.
NOTE: +12 volts will not be present when the vehicle is
traveling above the speed the speed switch is
programmed for.
8
7 6
5 4
3 2
1
A
B
C
D
FRONT VIEW OF I/O MODULE
CONNECTOR
REFER TO MP84.3180
EXHAUST
AXLE AIR IN
[ HCV ]
L
E
F
T
BY-PASS
VALVE
R
I
G
H
T
AIR
IN
BAG
R
BAG
PSW
BY-PASS
VALVE
BAG
CHECK VALVES
AIR SUPPLY
AIR BAGS
LINE TO
CONTROL
HEIGHT
LINE FROM
VALVES
3.400"
FRONT AIR MANIFOLD
REAR VIEW
SWITCHES (2)
PRESSURE
PRESSURE REGULATOR
REFER TO MP74.2670A
Step 3b. One or
more air bags
do not deflate.
The other air
bags do deflate.
First, make sure the exhaust ports for the bags that will not
exhaust air are not plugged with dirt or debris. Clean if
necessary.
Use caution as the air will start to dump after
cleaning the ports if the DUMP light is still flashing.
With
the DUMP button light flashing, check the LED for any lower
valve that controls an air bag that did not exhaust air.
If the
LED is lit,
check for +12 volts between the two pins of the
MIOM connector. If +12 volts is present, replace the valve. If
+12 is not present the issue is the wires or their connections
in the plug. Fix if possible or replace the MIOM.
If the LED is
not lit,
turn the engine off,
unplug the valve, the main MIOM
connector and the 2 pin MIOM plug for high current and
ground. Wait about 10 seconds, then plug the main connector
and the 2 pin connector back in. Do not plug the valve back
in. Turn the ignition on. If the lower valve LED now comes on,
replace that lower valve. If the lower valve LED still does not
come on, replace the MIOM.
*
RIGHT FRONT TRAVEL
RIGHT FRONT LOWER
RIGHT FRONT RAISE
AIR COMPRESSOR
LINK LIGHT
LEFT FRONT LOWER
LEFT FRONT TRAVEL
SYSTEM LATCH
LEFT
FRONT
RAISE
REFER TO MP84.3180