US Shift 4R70W, Installation And Operation Manual

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Adaptation for Factory-Equipped Transmissions
It is possible to use the Quick 2 controller in a vehicle which was originally
equipped with one of the intended transmissions. This could be done in
conjunction with an engine management system upgrade that no longer
supports the transmission. Use of the controller for this purpose allows flexibility
in choosing the engine management system, in addition to the increased
control, performance, and transmission durability afforded by Quick 2. If you
retain the stock PCM/VCM, it can probably be modified or re-flashed to disable
the transmission functionality.
Identifying the Terminals of an Unknown Throttle Position Sensor
This is a procedure for identifying the correct terminal connections of any
potentiometer-style throttle position sensor (almost all three-terminal TP
sensors). A DVOM or analog Ohmmeter is required.
1. Set the meter to resistance mode and set it to a scale that can read up to 10K
or 20K Ohms (if it is not auto-ranging). Please keep in mind when setting up and
reading the meter that "K" means thousands of Ohms. In other words, 15K
Ohms is the same as 15,000 Ohms.
2. Connect the meter to two pins at a time while operating the lever or cam of
the TPS. Watch the meter while rotating the sensor. Check all three pairs of pins
until you find a pair that does not change resistance when you rotate the sensor.
The two pins that do not change resistance are the fixed ends of the resistance
element (+5V and ground). The remaining pin that did change is known as the
"wiper". It is the moving contact that slides along the resistance element to give
the varying voltage. This is the output terminal of the sensor and should be
connected to our green wire (Vehicle pin 3).
3. Next, with the sensor at the idle or closed throttle position, measure the
resistance between the wiper (output) and each of the end terminals (the two
whose resistance did not change in step 2) of the sensor. The end terminal with
the lowest resistance to the wiper (at idle) is the ground terminal, and should
connect to the black main ground wire of the controller (Vehicle pin 16). The
terminal with the higher resistance to the wiper is the 5 volt reference input to
the sensor and should connect to the orange wire (Vehicle pin 11) in our
harness.
General Guidelines for setting up Throttle Position Sensors
The linkage to a throttle position sensor should use most of the rotating range of
the throttle position sensor. This can be adjusted by changing the ratio of the
linkage. Also, please make sure that a small amount of the sensor's travel is
being used at idle. You will want a TPS voltage at idle of at least 0.35 volts. This
is done to allow the controller to detect problems with the TP sensor. For
instance, if the sensor becomes disconnected or the linkage falls off, the TPS
voltage will fall below the set idle threshold. If the TPS voltage goes below the
idle threshold, the controller assumes that the TPS is bad and will switch to
failsafe line pressure and default shift points. This is done to prevent damage to
the transmission from low line pressure and will provide a safe "limp home"
mode.