MI91.1265
10SEP07
625 TROUBLE SHOOTING STEPS
MANUAL OPERATION
PART 16. THE YELLOW LEVEL INDICATORS ON THE TOUCH PANEL
1. The yellow lights do not correspond to the position of the vehicle, such as the right
a. There are four yellow LEDs on the sensing unit board. These LEDs should correspond to the yellow level
A lit yellow level light indicates that side or end is low. When all of the yellow lights are out, the vehicle should be
level. One or two yellow lights may be on at one time but opposing yellow lights should never be on. The sensing
unit is located in the control box. Because the control box can be mounted with the clear Plexiglas cover pointing
in any of four directions, the sensing unit must be programmed for direction and also the type of suspension, air or
spring. Most systems that are installed by the vehicle manufacturer have a preprogrammed sensing unit. After
market systems will most likely have a programmable sensing unit. Replacement control boxes will usually be a
generic type with a programmable sensing unit. Replacement sensing units will be programmable. When replacing
a control box or sensing unit, refer to instruction sheet ML31215 for detailed instructions for programming the
side of the vehicle is low but the left side yellow level indicator light is on.
indicators on the touch panel. If they do not, the sensing unit is not programmed properly. If the sensing
unit is programmable, reprogram the sensing unit. If the sensing unit is not programmable, the position
of the complete power unit assembly will have to be changed. If this is not reasonable to do, the sensing
unit will have to be replaced with a programmable one.
b. If the sensing unit LEDs and the touch panel lights correspond, the sensing unit
may be out of adjustment. There is an adjustment nut and screw on the outside
of the control box for the sensing unit. Refer to the maintenance sheet for sensing
unit adjustment procedures. Minor, gentile movement of the adjustment nut and
screw work best.
2. No yellow level indicators on the touch panel will come on. The yellow LEDs on the
sensing unit board are NOT working.
a. Unplug the sensing unit. Use a test light to check pin 1 on the board for +12 volts
and pin 6 for a ground. If these pins are OK, replace the sensing unit. If either pin
is not working, replace the control box.
3. No yellow level indicators on the touch panel will come on. The yellow LEDs on the
sensing unit board ARE working.
a. Unplug the sensing unit. Use a test light to ground pins 2 (rear), 3 (right side),
4 (front) and 5 (left side). If the appropriate yellow lights onthe touch panel come
on, replace the sensing unit. If the appropriate yellow lights do not come on,
replace the control box.
4. Yellow level indicator lights on the touch panel will not go out or opposing yellow
indicator lights are on.
a. Compare the yellow LEDs on the sensing unit board to the yellow indicators on the
touch panel. If the LEDs on the sensing unit board match the yellow level lights on
the touch panel, replace the sensing unit. If the LEDs on the sensing unit board
DO NOT match the yellow lights on the touch panel, replace the control box.
SEE: MI91.1155 & MP85.6148
SEE: MP85.6148
SEE: MI91.1155 & MP85.6148
PART 15. Continued. . .
SEE: MP85.091C
replace the control box. If the LED goes out, the warning switch wire(s) for the LED(s)
the 12 pin gray connector from the back of the control box. If the LED remains on,
customer service. If the LED stays on with the warning switch unplugged, unplug
in the jack may be bad. If a new switch does not fix the problem, contact HWH
lit LED. If the LED(s) go out, the problem is the warning switch. NOTE: The magnet
2. If a warning switch LED is on, unplug the warning switch for the jack(s) that have a
that are on are shorted to ground.
MP85.091C
STUD
WARNING
SWITCH
PILOT AIR DUMP
6235
LEFT REAR
4000
4200
9300
6231
6230
9301
PRESSURE
SWITCH
A
B
CONNECTION
C
A
B
6231
9300
9301
6230
RIGHT REAR
MP85.091C
08AUG07
3000
6235
3200
PRESSURE
SWITCH
SWITCH
WARNING
A
B
ELECTRICAL CONNECTION DIAGRAM
625 SERIES SINGLE STEP LEVELING SYSTEM
TOUCH PANEL - JACK WARNING LIGHTS AND PRESSURE SWITCHES
PILOT AIR DUMP - PARK BRAKE - MASTER WARNING LIGHT AND BUZZER
WARNING
SWITCH
PRESSURE
6111
BUZZER
TO HWH
GROUND
6111
PARK BRAKE
SWITCH
DIODE
7699
DIODE
+
7699
7699
WARNING
MASTER
LIGHT
LEFT FRONT
6110
5AMP
FUSE
1200
SWITCH
1000
A
B
6235
9001 - TO
PARK BRAKE
LIGHT
9000
_
9000
7699
NOT IN
TRAVEL
BRAKE
SLOPE
EXCESS
HWH COMPUTERIZED LEVELING
TOUCH PANEL
CAUTION!
SECURELY BEFORE REMOVING TIRES OR CRAWLING UNDER VEHICLE.
UNDERSTAND OPERATOR’S MANUAL BEFORE USING. BLOCK FRAME AND TIRES
TO IGNITION
TO ACCESSORY
6120
AUTO
LEVEL
STORE
AUTO
EMERGENCY
STOP
MODE
PARK/
R
RETRACT
EXTEND
MANUAL
RETRACT
EXTEND
RIGHT FRONT
PILOT DUMP
CONNECTION
DIAGRAM - 625 SERIES
MANIFOLD - PUMP AND
MASTER RELAYS
LEVELING SYSTEM - LEVELING
GRAY
4 PIN
12 PIN
BLACK
8 PIN
12 PIN
BLACK
BROWN
12 PIN
GREEN
12 PIN
GRAY
PRESSURE
SWITCH
6235
SEE ELECTRICAL CONNECTION
6230 - 6231
9301
9300
WARNING
SWITCH
2000
2200
BY OEM
A
B
sensing unit. No special tools are needed.
ARE NOT FUNCTIONING PROPERLY.
Indicator light
"EXCESS SLOPE"
UNDERSTAND OPERATOR’S MANUAL BEFORE USING. BLOCK FRAME AND TIRES
SECURELY BEFORE REMOVING TIRES OR CRAWLING UNDER VEHICLE.
HWH COMPUTERIZED LEVELING
EXTEND
RETRACT
COMPUTER-CONTROL
625S SERIES LEVELING SYSTEM
CONTROL IDENTIFICATION
CONTROL FUNCTIONS
Manual button
dumping air from the vehicle suspension.
"MANUAL DUMP" BUTTON:
the automatic store function.
STORE INDICATOR LIGHT:
during the automatic leveling function.
AUTO LEVEL INDICATOR LIGHT:
INDICATOR LIGHTS
button is being pushed.
start the automatic leveling function.
will retract their respective jack pairs to lower the vehicle.
extend their respective jack pairs to lift the vehicle.
RETRACT BUTTONS (DOWN ARROWS):
EXTEND BUTTONS (UP ARROWS):
CONTROL BUTTONS
when the hand/auto brake is not set and the "AUTO LEVEL"
"NOT IN PARK/BRAKE" LIGHT:
four jacks at the same time.
"AUTO STORE" BUTTON:
"AUTO LEVEL" BUTTON:
any leveling system operation.
"EMERGENCY STOP" BUTTON:
This light will flash during
This light will flash
This indicator will light
This is a manual button for
Push this button any time to
These buttons will
Push this button to retract all
Push this button to stop
These buttons
"AUTO STORE"
AUTO LEVEL
Indicator light
Indicator light
"TRAVEL MODE"
Indicator light
Indicator light
"NOT IN PARK"
CANCEL Button
AUTO LEVEL/STORE
"AUTO LEVEL"
Button
STORE
Button
LOWER LEFT SIDE
Manual button
RAISE LEFT SIDE
STOP
CAUTION!
DUMP
MANUAL
EMERGENCY
LEVEL
AUTO
STORE
AUTO
PARK/
NOT IN
MODE
BRAKE
TRAVEL
SLOPE
EXCESS
R
"MANUAL DUMP"
Button
HYDRAULIC LEVELING FOR DETAILED EXPLANATION.
level. SEE OPERATOR’S PROCEDURES - AUTOMATIC
When all four yellow LEVEL lights are out, the vehicle is
It will be on when any one or more jacks are extended
or "ACC" position, the system is on, and the jacks are
They are functional only when the ignition is in the "ON"
yellow level indicators are jacks down WARNING lights.
The four red lights surrounding the
No more than two lights should be on at the same time.
indicates that its side, end, or corner of the vehicle is low.
level sensing indicators. When a yellow light is on, it
The four yellow indicating lights are
This indicator light will be on
This indicator will light when
INDICATOR LIGHTS (CONTINUED)
light mounted in the dash separate from the touch panel.
MASTER "JACKS DOWN" WARNING LIGHT:
when the ignition is on, when the jacks are retracted and
the leveling system cannot level the vehicle.
It will sound if the master "JACKS DOWN"
This is a jacks down warning.
and the ignition is "ON".
there are no red WARNING lights on.
"TRAVEL MODE" LIGHT:
BUZZER:
warning light is on.
extended 1/4 to 1/2 inch.
LEVELING LIGHTS:
"EXCESS SLOPE" LIGHT:
WARNING LIGHTS:
10AUG07
MI91.1155
This is a
Manual button
LOWER REAR
Manual button
RAISE REAR
(4) yellow
Indicator light
LEVEL SENSING
Manual button
LOWER RIGHT SIDE
Manual button
RAISE RIGHT SIDE
Indicator light
JACK DOWN
Manual button
RAISE FRONT
Manual button
LOWER FRONT
MANUAL
RETRACT
EXTEND
(4) red
ADJUSTMENT
NUT (7/8" or 3/4")
ADJUSTMENT NUT
MAY BE DIFFERENT
LED’S - LOCATION
ADJUSTMENT SCREW
SENSING UNIT ADJUSTMENT
MAINTENANCE/SERVICE
adjustments first, then hold the adjustment nut from moving
while making the A-C adjustment.
TOP VIEW - SENSING UNIT
NUT
MP45.271M
ADJUSTMENT
BOX WALL
CONTROL
B
D
C
A
wrench and a philips screw driver will be needed.
needed. A 7/8", 3/4" or 5/16" socket w/driver or box end
Touch Panel, manual adjustments to the Sensing Unit are
properly adjusted. If there are yellow LEVEL lights lit on the
are no yellow lights lit on the Touch Panel, the sensing unit is
With the vehicle level according to the bubble level, if there
Control Box. If two LED’s are on, it is best to make the B-D
be a problem with the Sensing Unit or the mounting of the
be turned more than 3/4 turn to turn the LED out, there may
to be turned more than 1/2 flat or the adjustment screw has to
screw will turn out LED’s A and C. If the adjustment nut has
the adjustment nut to turn out LED’s B and D. The adjustment
to the drawing below. The Sensing Unit is adjusted by turning
There are four LED’s on the Sensing Unit, A,B,C and D. Refer
Control Box is mounted to the power unit/valve assembly.
The Sensing Unit is mounted inside the Control Box. The
level the vehicle until the bubble is centered.
level, ignoring the yellow LEVEL lights on the Touch Panel,
that is to be level. Using the Leveling System and the bubble
the freezer floor or upon whichever surface within the vehicle
Level the vehicle by placing a bubble level in the center of
the vehicle, the front is still low. This means the front
"tweaking" process until the system levels the vehicle
touch panel. Recheck with a level. Repeat the
relevel the vehicle using the yellow level lights on the
the front up more. Again, unlevel the vehicle then
the front yellow light to stay on slightly longer to bring
instructions for LED’s A, B, C, and D. This will allow
the OPPOSITE direction that is given in the above
Move the adjustment for that light very, very, slightly in
which sensing unit light is the front light, A-B-C or D.
yellow level light is turning off too soon. Determine
SIDE VIEW - CONTROL BOX
SCREW (Phillips or 1/4")
ADJUSTMENT
properly.
NUT (5/16")
ADJUSTMENT
MP85.6148
19FEB07
Example: After the initial adjustment and releveling
sensing unit, ignoring the LED’s on the sensing unit.
yellow level lights go out, instead just "tweak" the
needed, DO NOT try to adjust the sensing unit until the
LEVEL lights. Recheck the level. If more adjustment is
lights are on. Level the vehicle according to the yellow
vehicle to an unlevel position so one or two yellow
IMPORTANT: When all 4 LED’s are off, move the
If LED (D) is lit: Turn the adjustment nut CLOCKWISE
If LED (B) is lit: Turn the adjustment nut COUNTER
If LED (C) is lit: Turn the adjustment screw CLOCKWISE
If LED (A) is lit: Turn the adjustment screw COUNTER
NOTE: If opposing LED’s are lit, there is a problem with
until the LED is off.
CLOCKWISE until the LED is off.
until the LED is off.
CLOCKWISE until the LED is off.
the Sensing Unit.
MI91.1155
MP85.6148
IMPORTANT: The sensing unit has an accuracy tolerance of
± 1 inch side to side and 5.4 inches front to rear on a 36’ vehicle.
