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MegaShift 4L60E Wiring
The 4L60E is controlled through 14 pins. These are:
|L||Temperature Sensor Signal|
|M||Temperature Sensor GND|
|N||Pressure Switch A (aka. Pin A)|
|R||Pressure Switch B (aka. Pin B)|
|P||Pressure Switch C (aka. Pin C)|
|n/a||2WD/4WD Input (ground for 4WD)|
|n/a||Vehicle Speed Sensor (VSS) - has its own 2-pin connector|
|A||Sol A (1-2/3-4) Switched GND||On/Off||20-40 Ohms (0.75 Amps Max.)|
|B||Sol B (2-3) Switched GND||On/Off||20-40 Ohms (0.75 Amps Max.)|
|C||Pressure Control Solenoid High||Power (nominal +12V)||Switched 12V from harness|
|D||Pressure Control Switched GND||PWM (293Hz)||0 to 60% (3.5 - 4.6 Ohms at 20°C, 1.1 Amps Max.)|
|E||+12 Volt Power||High (nominal +12V)||Switched 12V from harness|
|U||Lock-Up Feel Solenoid Switched GND not always used|
|S||3-2 Sol Switched GND||PWM (50Hz)||(9-14 Ohms at 20°C)|
|T||Torque Converter Clutch Solenoid Switched GND||On/Off||20-40 Ohms (1.5 Amps Max.)|
The wiring inside the 4L60E transmission looks like this:
The corresponding AMPseal connections for the control/sense functions are:
|line pressure sensor||AD4||EGT2||27|
|Spare Output1 (LU Feel/Clutch)||PT7||VB1 (jumper)||11|
|Spare Output2 (Clutch)||PA0||VB2||12|
In addition there are:
|Power In (+12V)||1|
|Power Grounds||18, 19, 20|
On the GPIO, the connections are:
On MS-II controllers, the CAN paths are:
The CAN termination resistors are already in place on the MS-II and GPIO.
To wire the 4L60E transmission to the GPIO board, you need to make a number of connections:
Note that you need a 4.7 Ohm, 5 Watt (or more) resistor (such as Digi-Key 4.7W-5-ND, 34¢) on the pressure control solenoid wire from the trans connector pin D to the GPIO board's pin 33, and a 1N4001 diode placed between pin C and D on the 4L60E connector (the closer to the transmission connector the better). These cut the flyback spikes from the solenoid to manageable levels.
Any solenoid that is pulse width modulated (including the shift solenoid outputs and TCC, if they are PWM'd) require that you put a flyback diode on the solenoid. The illustrated instructions are here: Recirculation Diode Instructions. Install an external diode between that solenoid's voltage supply and the line going to the GPIO board. The banded end of the diode goes to the voltage supply wire, the non-banded end of the diode goes to the line to the GPIO board. Install the diode as close to the solenoid as is convenient. The 1N4001 diode is installed externally to avoid bringing high-voltage noise into the GPIO. 1N4001 diodes are available at virtually any electronics supply shop. Without this external diode in the PWM circuits, you may damage some internal components.
The four resistors for the LEDs can be 330 to 390 Ohms, 1/4 Watt.
If you want a 'mode selection switch' to force auto mode or enable manual mode, you can do this with a switch and two diodes (1N4001 or equivalent):
(This circuit only works with 'Shift Button Polarity' = "active low".)
When the mode switch is closed, auto mode will be used, regardless of what you do with the shift buttons. If the mode switch is open, pushing either the upshift button or downshift button will put you in manual mode (and pushing both OR switching the mode select switch to auto will put you back in auto mode).
If you are looking for a 4L60E harness connector, try a scrap yard, or here: www.currentperformance.com/Connectors/LS1_LS6.html
The 4L60E uses three types of sensors:
|Shift Pattern||Sol A (1-2/3-4)||Sol B (2-3)||3-2 Sol||TCC Sol (LU)||LockUp Feel***||Pressure Control solenoid Sol||Ratio|
|Park||ON||ON||ON #||ON *||N/A|
|Reverse||ON||ON||ON #||ON *||2.294|
|Neutral||ON||ON||ON #||ON *||N/A|
|1st||ON||ON||ON #||ON *||3.059|
|2nd||OFF||ON||ON ***||ON/OFF**||ON #||ON *||1.625|
|3rd||OFF||OFF||ON ***||ON/OFF**||ON #||ON *||1.000|
|4th||ON||OFF||ON ***||ON #||ON *||0.696|
|LU||ON||OFF||ON ***||ON**||ON #||ON *||N/A|
|Solenoid A||20 - 40||43.0|
|Solenoid B||20 - 40||43.0|
|3-2||9 - 14||14.1|
|TCC||20 - 40||56.9|
|LU Feel||not known||not known|
|Pressure Control||3.5 - 4.5||8.1|
Pressure Switch Manifold
The pressure switch manifold (PSM) is a multiple switch assembly consisting of 3 normally open (NO) pressure switches and 2 normally closed (N/C) pressure switches.
Fluid from various hydraulic control circuits is fed to this the pressure switch manifold which allows the ECU to determine which gear the shift lever is currently shifted into (not necessarily the actual gear the transmission is in). The switch contacts are normally open and close when fluid pressure causes them to. Depending upon the circuit, the switch may provide a ground path when closed. The table below shows a pin that is grounded by the PSM as a "0", while an open circuit shows a 12 (volts).
|Gear||Pin N||Pin R||Pin P|
|A||Sol A (1-2/3-4) Switched GND|
|B||Sol B (2-3) Switched GND|
|N||Pressure Switch A|
|R||Pressure Switch B|
|P||Pressure Switch C|
|M||Temperature Sensor GND|
|L||Temperature Sensor Signal|
|S||3-2 Solenoid Switched GND|
|D||Pressure Control Solenoid Switched GND|
|C||Pressure Control Solenoid +12V|
|U||LU Feel Solenoid Switched GND|
|T||TCC Solenoid Switched GND|
Main Line Pressure Tap
MegaShift has a line pressure sensing/logging function built it. It is Digikey MSP6907-ND for $114. It's a 0.5-4.5 Volt output (accuracy &plusminus;5 psi), and has just a three wire hookup:
It has a 1/8 NPT fitting - the same as the transmission port. However, a 90° elbow, or maybe even some tubing, will be required in most installs to keep the sensor away from the transmission tunnel.
4L60E Temperature Sensor Output