2016/07/29
Changing Direction and Speed (SEBU9388-15)
SMCS - 1000, 3030, 3100, 4269, 5462, 5705, 7000, 7300, 7451
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NOTICE
T avoid striking overpasses, electrical power lines and
To
obstructions, always lower the body before moving the
machine.
NOTICE
The machine must be stopped and engine at low idle before
changing directions.
After moving the shift lever,
r do not accelerate until after hearing
or feeling the transmission clutches engage.
Illustration 1
(1) Transmission control
g01519384
Make sure that the machine is stopped and that the engine is at low idle when you move the transmission control to the P position. When the
transmission control is in the P position, the transmission is in neutral and the parking brake is engaged.
d. Whe
When the transmission control is in the N
position, the transmission is in neutral, the parking brake are not engaged, and the wheels are free to roll.
Make sure that the machine is stopped and that the engine is at low idle when you change direction between forward and reverse, or between
reverse and forward.
When the machine is at a stop and the transmission control is moved to any forward selection, first gear is engaged. Below ground speed of
approximately 6 km/h (4 mph), the machine will be in torque converter drive.
When the engine accelerates and the ground speed increases, the transmission automatically upshifts. Above ground speed of approximately
6 km/h (4 mph) and during other forward gears, the lockup clutch will be engaged. Then, the machine is in direct drive. During shifts, the machine
will be in torque converter drive.
While the machine is in motion, moving the transmission control to a higher forward selection will not force an upshift. Shifting of the transmission is
governed by ground speed.
When the ground speed and the engine speed are reduced by an increased load or by deceleration, the transmission automatically downshifts.
The transmission downshifts one gear at a time to select the correct gear.
A downshift inhibitor prevents the machine from forcing a downshift. When the machine is in motion and the transmission control is moved to a
lower forward selection, the transmission will not force a sudden downshift. The transmission will not downshift until the proper ground speed is
achieved.
Shift Inhibiting
The Transmission/Chassis Electronic Control Module (ECM) performs most of the transmission control and torque converter lockup functions. The
Transmission/Chassis ECM receives input signals that describe the position of the body and the position of the transmission control. The input
signals are used to control the shifting of the transmission and torque converter lockup.
Shifting is limited in the following situations: limiting machine speed, engine overspeed protection, coasting in neutral, management of directional
shifts, limiting top gear, reverse neutralizer and limiting body up gear.
Reference: See Service Manual, "Transmission Electronic Control System" for additional information.
Limiting Machine Speed
Cold Mode for the Transmission - This limits the top gear of the machine until the oil temperature in the transmission reaches operating
temperature range. When the oil temperature in the transmission is below 40 °C (104 °F), the transmission will not shift above FIRST gear.
Engine Overspeed Protection
If the engine speed reaches 2300 rpm, the alert indicator and the action alarm will activate. When the engine speed reaches 2300 rpm, the
Automatic Retarder Control (ARC) will automatically begin to apply the rear service brake (if the machine is equipped with ARC). If the engine
speed reaches 2700 rpm, the transmission will up shift to the next higher gear. If the transmission is in the highest gear and the engine speed
reaches 2700 rpm, the torque converter will shift into TORQUE CONVERTER DRIVE to protect the powertrain from engine over speed.
NOTICE
Do not exceed 2300 rpm or engine damage can result.
Coasting in Neutral
The transmission will not shift into NEUTRAL if the machine speed is above 8 km/h (5 mph).
Management of Directional Shifts
If the transmission is in a forward gear and the transmission control is moved into the R position, the transmission will remain in forward gear until
the machine speed is below 8 km/h (5 mph). Then, the transmission will shift into neutral. The transmission will not shift from neutral into reverse
until the machine speed is below 3 km/h (2 mph).
Limiting Top
T Gear
The transmission will not shift to a gear above the selected top gear limit. The machine comes from the factory with the highest gear as the top
(ET) to change the top gear limit.
gear limit. Use the Electronic Technician
T
Reverse Neutralizer
The reverse neutralizer prevents the transmission from engaging in reverse gear with the hoist control in the RAISE position or the hoist control in
the LOWER position.
Note: The transmission will engage in reverse gear with the body UP and the hoist control in the FLOAT
OA position and the transmission will engage
in reverse gear with the body UP and the hoist control in the HOLD position.
The reverse neutralizer function activates when the following conditions occur simultaneously:
The hoist control is in the RAISE position or the LOWER position.
The transmission control is in the R position.
While the reverse neutralizer is active, a NEUTRAL value is sent to the transmission ECM.
Once the reverse neutralizer is active, the reverse neutralizer will remain active until any of the following conditions occur:
The transmission control has been moved to any of the forward selections.
The transmission control has been moved into the N position.
Limiting Body Up Gear
This function limits the gear of the machine while the body is up. The gear is limited until the body position sensor tells the ECM that the body is
DOWN. The chassis ECM prevents upshifting to any gear higher than the stored value. The value of the gear limit is programmable by the service
personnel. Use the ET service tool. The allowed range for this gear limit is FIRST gear to THIRD gear. The value of the factory setting for the gear
limit is FIRST gear. The gear limit must remain set to first gear on machines with a “CE” mark (plate). The “CE” mark is on machines that are
compliant with the requirements of the European Union.
PSP-000636F2
2021/12/27
05:29:19+06:00
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