2006 FORD TRANSIT start stop button

Resistance Ladder

Resistance Ladder Circuit
DescriptionItem
To Green / White Wire1
Stop Engine2
RPM 1 on / off or Variable Control 'Idle'3
RPM 2 on / off or Variable Control 'Negative (-)'4
RPM 3 on / off or Variable Control 'Positive (+)'5
RPM control Armed or Increased Idle on / off6
The resistance ladder circuit acts as a potential
divider. The PCM has an internal reference
voltage of 5 volts. Current passes through an
internal 320 ohm resistor (not shown above) prior
to passing through the resistance ladder. There
is also a (second) 220 nF capacitor internally
within the PCM between the 320 ohm resistor &
ground (not shown above) & this is to reduce
EMC effects.
With all the switches open there a total resistance
in the green/white loop of approx 4330 ohms &
this corresponds to normal driving operation (as
does short circuit – the condition prior to the loop
being cut).
Starting from the right of the diagram, when the
key switch is closed only 2110 ohms is in the
circuit & the PCM software recognizes this as the
RPM mode being armed & ready for operation
(Key switch closed = on, open = off). A key switch
is recommended in this position for a couple of
reasons:
•If the control box is located externally on the
vehicle, the requirement for a key avoids any
passers by being able to put the vehicle into
RPM Speed Control mode by simply pressing
a button.
•Using a key switch where the key can be
removed in either the ‘on’ or ‘off’ condition
could be used as an aid to anti theft. If the
operator uses a key to put the vehicle into
RPM Speed control mode & then removes the
key, then the vehicle cannot quickly & easily
be taken out of RPM speed control mode. If
a foot pedal is pressed while in either the 3
speed or variable speed modes, the vehicles
engine will stall & therefore the vehicle can not
easily be driven away & stolen.
When in 3 speed mode pressing any of the
middle 3 switches (with the feature armed) results
in the engine RPM jumping to the corresponding
RPM value held in memory (defaults of 1100, 1600
or 2030rpm) for the 3 switch positions. A second
consecutive press of the same button returns to
normal idle.
When in variable speed mode the same 3 buttons
act as ramp up, ramp down & return to idle
selections respectively.
FordTransit 2006.5 (April 2006–)
Date of Publication: 12/2006
4 Electrical
16065432E88295711

The software in the PCM responds to the change
of state, so it is recommended that these 3
middle switches be non-latching push button
micro switches. When going from idle to an
elevated RPM the execution of the command
will occur as the button is released. When going
to idle the execution of the command occurs as
the button is pressed.
The final button (the one on the left in Fig. 4) acts
as an ‘emergency’ vehicle engine stop. It is
recommended that this be a red & oversize
non-latching micro switch button. The execution
of this command will occur as the button is
pressed.
All wiring connecting the PCM to the resistance
ladder control box should be shielded & twisted
(33 twists / m) to reduce EMC effects
All resistors should have a tolerance of +/- 5% or
better
Switch contact, connectors & loom (loom
between the green/white wires & the control
box) total resistance must be no greater than 5
ohm max.
The PCM to resister ladder control switch box
loom should not come within 100mm of any other
harness, especially any carrying heavy loads.
Designs which do not require all the button
switches must still have the complete resistor
network with the switches positioned correctly
within the network.
The resistance ladder is acting as a potential
divider
The 220 nF capacitor is used in the circuit to
reduce EMC effects on the system
A suitable two way quality connector should be
used to connect the control box to the two
green/white wires
How to change the default settings
By default, when the feature is first enabled
(either via factory order or via dealer IDS tools),
it will be set to the 3 speed mode of operation
with preset RPM values of 1100, 1600 & 2030rpm
for the 3 speeds.
There are two methods by which these defaults
can be modified:
1.via the IDS diagnostics system at a Ford dealer
(there may be a charge for this)
2.via an inbuilt vehicle ‘learn mode’
Via the IDS system the mode of operation can
freely be changed between any of the 3 modes
of operation, the feature can even be turn off
(disabled). The 3 default RPM speeds can also
be modified.
Via the vehicle ‘learn mode’ the 3 speed mode
& the variable speed mode can be freely
interchanged, however it is not possible to select
the idle up speed mode via the vehicle learn
mode. The 3 default RPM speeds can also be
modified via ‘learn mode’
It is not possible via either method above, to
change the step value of 25rpm per press or the
250 rpm per sec for a held down button, in the
variable rpm speed mode.
Via IDS The RPM Speed Controller menu is under
the tool box tab, then Powertrain, then service
functions, then PCM. The IDS on screen menus
will guide the dealer through the options & setup.
How to enter vehicle ‘Learn mode’
1.Make sure that the RPM Speed controller
switch box is connected but turned off (not
‘armed’)
2.Start the engine (vehicle out of gear & no foot
pedals being pressed, handbrake on)
3.Wait a couple of seconds for the instrument
panel start up diagnostic lights to extinguish
4.Press & release the clutch pedal
5.Press & release the brake pedal
6.Repeat steps 4) & 5) a further four times
(clutch & brake pressed a total of five times
sequentially each)
NOTE: Steps 4) to 6) have to be started within
10 seconds of the engine start
The vehicle should now be in ‘learn mode’
How to Select between modes
1.Enter ‘learn mode’ (see directions above)
2.Arm the RPM speed controller (turn the key
switch to ‘on’)
If the vehicle is already in 3 speed mode (the
initial default):
3.Press & release the brake pedal five times
The vehicle should now be in variable speed
mode. The new settings can be saved & learn
mode exited (see below)
Alternatively
4.Press & release the brake pedal once
The vehicle should now be in 3 speed mode.
The new settings can be saved & learn mode
exited (see below)
Using this method it is easy to change between
these two modes of operation for the RPM
speed controller
NOTE: If the engine stalls out at the initial brake
pedal input then the vehicle was not in, or has
dropped out of ‘learn mode’ & you will have to
restart the procedure.
FordTransit 2006.5 (April 2006–)
Date of Publication: 12/2006
4 Electrical
161

How to change the 3 pre-set default
RPM values in the 3 speed mode
1.Enter ‘learn mode’ (see directions above)
2.Arm the RPM speed controller (turn the key
switch to ‘on’)
3.Press & release the brake pedal once
4.Press & release the RPM button that requires
re-programming
5.Use the accelerator pedal to rev the engine to
the new desired RPM speed & hold at this
speed (only speeds between 1200 to 3000
rpm can be selected in 3 speed mode)
6.Press & release the same RPM button to reset
the stored RPM speed to the current engines
RPM
7.Release the accelerator pedal
8.Repeat steps 4) to 7) for the remaining RPM
buttons
The 3 RPM speeds should now be
re-programmed to the new RPM speeds. The
new settings can be saved & learn mode exited
(see below)
NOTE: If the engine RPM responds to the initial
RPM button press, then the vehicle has not
entered ‘learn mode’ correctly & you will have to
restart the procedure. If the engine stalls out at
the brake or accelerator pedal inputs then the
vehicle was not in, or has dropped out of ‘learn
mode’ & you will have to restart the procedure.
How to save new settings & exit
from ‘Learn mode’
1.From within the ‘learn mode’ & with the RPM
Speed Control switch box ‘armed’, press the
clutch pedal repeatedly until the engine stalls.
2.Restart the engine & test the new settings,
repeat above procedures if necessary
NOTE: The engine stalling indicates that the
settings should have been saved & the vehicle
has exited from ‘learn mode’. Learn mode
however is very specific that the exact steps are
taken in the correct order & within certain time
limits otherwise the learn procedure fails & it may
take several attempts to get this order & timing
correct & a successful modification from the
default settings.
Some Reasons why RPM speed
Control operation may stop or fail
The RPM Speed control software monitors
vehicle information during operation in RPM
speed control mode & will drop out of RPM speed
control and / or stall the engine should any
adverse signals be detected. For example:
•If the engine temperature becomes too hot
then RPM speed control will stop in order to
protect the engine.
•If the engine oil light illuminates then RPM
speed control will stop in order to protect the
engine
•If the low fuel level light illuminates then RPM
speed control will stop so that the vehicle can
be driven to a refueling point.
•If the vehicle speed exceeds approx 2.5 mph
wile in 3 speed or variable speed modes, then
RPM speed control may stop. RPM speed
control should normally be operated with the
hand brake on, but some uses may require a
low level of vehicle ‘creep’ during RPM speed
control operation. Note that there is no sensing
of the park brake on this version of RPM speed
controller to facilitate this type of operation.
•The software monitors for ‘stuck on’ buttons
on the control switch box, this may result in
RPM speed control being halted. A button that
is held down for too long may be registered
by the software as a ‘stuck’ button.
•The software monitors the foot pedals, if
depressed these may stall the engine if in 3
speed mode or variable speed mode (does
not apply to idle up speed)
•If the control switch box circuitry significantly
exceeds 2110 ohms or there is a short circuit
then RPM speed control will not be possible.
•If a PTO conversion has been attempted on a
vehicle with a non ABS braking system then
RPM speed control will fail due to vehicle
speed being registered via a transmission
speed sensor and / or the need to press the
clutch in order to put the vehicle in gear while
in RPM speed control mode.
4.14.10 Adding Connectors,
Terminals and Wiring
Additional Rear Speakers
NOTE: The connectors on the Instrument Panel
harness (14K024) and the main harness (14401)
are reversed between Left Hand Drive (LHD) and
Right Hand Drive (RHD) vehicles, hence different
sets of terminals/wires are required to cover all
the markets.
FordTransit 2006.5 (April 2006–)
Date of Publication: 12/2006
4 Electrical
162