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Compushift 3


5.0 average, based on 4 reviews

This product is currently out of stock

Product Information

The latest generation of the Compushift is here and its better than ever !

Brief Description of Operation.

The compushift is a stand alone ECU that allows you to control the electronic version of the ZF 4HP22/24, it takes various inputs from the vehicle and uses this data in conjunction with shift maps to decide when to shift, how hard to shift and when to lock the torque converter etc. Whats great about this system is that you can easily adjust all these variables yourself very easily using the free phone app. This is very nice for the LandRover and conversion world where you can have a variety of engines in different weight vehicles often doing very different jobs so you can adjust the transmission to suit how you want it to drive.

The ECU will need various inputs depending on the application :

Shifter position, the ECU needs to know which position the shifter is in, this can be done with either the Disco 2 XY switch or with our potentiometer system, Note the Disco 2 type switch can only be used on a Disco 2 V8 or TD5 autobox as these have a different selector shaft, marked with an 'O' stamped on the end of the shaft.

Clean 12 Volt switched feed

Throttle Position Sensor (TPS). The ECU needs to know the throttle position, this signal takes the form of a 0 - 5 V signal which can come from either the existing vehicle TPS if you are converting a TD5 or TDCi or you can use a small linkage connected to the throttle mechanism and use this to activate a separate small TPS. On EFI V8's you can use the pot on the plenum chamber. On startup this needs to be calibrated but it's very easy, you just press the relevant button on the ECU or display and you have 5 seconds to fully stroke the throttle to max and back to zero, the signal "self calibrates".

Manifold Air Pressure (MAP). The vehicle will drive better if its connected to the MAP sensor on diesels or the vacuum sensor on petrols if it has one, the Compushift will work without this input but will drive better with.

Temperature Sensor, this is used for 2 reasons, the shift pressures are adjusted depending on the oil temp to allow for the changing viscosity and if the system is used with the optional display you can monitor this temp and check for overheating. The sensor can be fitted to one of the diagnostic plugs in the pump housing, location will be in the fitting instructions.


We have helped develop the Compushift for the conversion of the 2007 onwards TDCi Defender to Automatic but it can be used anywhere the ZF 4HP22/24 EH is used, i.e. Defender TD5 conversions, 2.8 TGV auto conversions, V8 competition vehicles. You can easily add tiptronic control and have total control over the torque converter lockup clutch. This system is perfect for the conversion world as you can adjust all the variables to suit your application to get the vehicle driving as you want it to drive.


Product Code: Comp3

Installation Information » (Click to Expand Collapse)


Installation instructions for fitting to the ZF 4HP22/24


In the Box there will be:


1          x          Compushift ECU


1          x          Wiring loom


1          x          TPS loom extension


1          x          Temperature sensor


If you  also purchase our Potentiometer shifter position switch you will also have:


1          x         Potentionmeter switch


1           x        Mounting bracker


1          x          Lever arm



The Parts in Detail


Compushift ECU


This is to be mounted in the cab in a relatively dry position; we usually put them on the middle seat cover so it’s under the centre console.


Wiring Loom


The large plug fits to the ECU


Next to the large plug are 2 wires, white / orange and white / brown -  these are used to switch the reverse and starter inhibit relays when you are using the potentiometer type position switch, more on this below.

The black round plug fits to the transmission.

The black 2 pin plug is for the ‘Fluid Temp Sensor’.

The plug labelled ‘TPS’ (throttle position sensor) must be wired to give a 0-5V signal to the Compushift ECU. On the TD5 and Tdci you can use the pot on the throttle pedal for this and you will just need to use 2 of the 3 wires, (use TPS extension loom) if the plug is removed from the pot and you look at the pins you will see they are labelled ABCD etc., connect the green wire to the wire that fits to pin F (signal wire), connect the green/white wire to the wire that fits to pin G (earth). On a V8 you can connect these 2 wires to the plenum chamber pot to get this signal, on a Tdi or 2.8 TGV you will have to fit a pot on either the pedal or injector pump. If you are adding a pot for this you will have to also use the green/red wire as the 5V feed.


You now have 2 plugs left, you will only be using one of these and this will depend which type of position switch you are using, if you are using the Disco 2 switch we will have removed a round 5 pin plug and fitted a plug to suit the D2 switch (note there is an additional change for this).  If you are using the newer potentiometer type switch you will use the straight 3 pin plug. Fit the relevant lead to the position switch you are using.


You now have 11 loose wires:


Red and black - this is the main feed, to be connected to a clean 12V switched feed, i.e. gets power when the ignition key is turned on. This feed can also be used to power the shifter illumination lights.


White/brown and white/blue - the transmission needs to vary clutch pack oil pressure according to the engine load, there are 2 ways to input this data to the ECU:-


  1. via the throttle position sensor or


  1. via the engine MAP sensor.  The MAP works much better and these 2 wires are for this purpose, the white/brown goes to 

ground and the white/blue goes to the MAP signal wire. More information is on this below.


White/red, White, White/black - These 3 wires can be connected to a momentary rocker switch or paddle switch to allow Tiptronic control, they are upshift, common and downshift.

Blue/orange and Blue/red - The Compushift will let you program many settings in a mode A and a mode B, mode A will be the normal default program, mode B can be programmed with different shift and pressure characteristics which could be a sport mode or tow mode, If the  Blue/orange wire is held to ground for 2 seconds using a momentary switch the ECU will switch to mode B parameters, the Blue/red will then get a 12V signal to indicate you are in mode B which can be used to light up a ‘sport’ light etc.

Purple/white - this wire emits a speed signal which can be used for a speedo or cruise control. Not required for the Compushift to function.

Brown - can be used to show engine rpm on display unit but is not required for the Compushift to function.



Temperature Sensor






Position Switch notes


There are 2 types of position switches that can be used with the Compushift, in the past we have used the Disco 2 switch, part number UHB100190 but this has got very expensive so we have looked at alternatives. We have had software written within the Compushift that allows us to use a linear potentiometer linked to the shifter to give a 0-5V signal.


Potentiometer type position switch




The potentiometer (pot) can be mounted to the shifter inside the cab or to the gearbox shift lever on the side of the autobox, just check the stroke length before mounting, it’s self -calibrating so just ensure you are not running out of stroke in Park or 1st gear.

The mounting position will depend on what type of shifter you have in the vehicle, if using our ‘standard’ type shifter, we supply brackets so it will fit like:


Disco 2 type position switch


If you are using the Disco 2 type shifter the mounting will look like:





The pot must be plugged into the 3 pin plug on the loom,


Compushift loom       Pot                  Function


White                         Yellow             Signal

White/red                   Red                 5v feed

White/black                Black              Ground




Search for ‘HGM’ in the ‘App Store’ on your smart phone or ipad, install both ‘CS Setup’ and ‘CS Flash’. Note you will need to be running iOS11 or later.


How to set ‘shift lever voltages’ when using the Potentiometer type switch,

Open ‘CS Setup’, tap ‘pair’, on the Home screen, tap ‘Vehicle Setup’, scroll down to ‘Transmission options’, tap ‘Shift Lever Calibration’.


Put the shifter into Park, tap ‘Set Park’

Put the shifter into Reverse, tap ‘Set Reverse’

Put the shifter into Neutral, tap ‘Set N’

Put the shifter into Drive, tap ‘Set D4’

Put the shifter into 3, tap ‘Set D3’

Put the shifter into 2, tap ‘Set D2’

Put the shifter into 1, tap ‘Set D1’


To check these positions are set correctly, go to the Home screen and tap ‘Diagnostics’, then ‘Transmission Diagnostics’ and check the ‘shift lever position’ agrees with the shifter lever.


Once all wiring is complete the TPS will need to be calibrated. This is done by taping ‘Engine setup’ on the home screen, then ‘TPS Calibration’, when you are ready, tap ‘Start’ and you then have 5 seconds to smoothly press the throttle to full then release to zero. You can check this has worked by tapping ‘Dashboard’ on the home screen and checking the ‘Throttle position’ moves when you press the throttle.


Reverse light switch and Inhibitor switch wiring


When using the Disco 2 type position switch the reverse lights and inhibitor switch wiring comes straight from the switch directly, this is not possible with the Pot type position switch. When the ECU sees the reverse position it gives a 12v feed to the white/orange wire. When the ECU sees the R, D, 3, 2 or 2 position it gives a 12v feed to the white/brown wire. These 2 feeds can be used to drive the relays for the respective switches.


Potentiometer type

Connect the white/orange wire from the Display/programmer to the green/brown wire, the 2 core wire that comes out of this relay needs to be wired through the reverse light circuit.


Connect the white/brown wire from the Display/programmer to the white/yellow wire, the 2 core wire that comes out of this relay needs to be wired through the low current side of the starter motor relay. This will ensure you can only start the engine in Park and Neutral.

Wire the black lead to earth.


Disco 2 type

Starter Inhibitor switch

Wire the labelled 2 core wire through the low current starter solenoid, so it will only start in Park or Neutral,

Reverse Light switch

Wire the labelled 2 core wire to the 2 wires from the reverse light switch from the manual gearbox.


Compushift Pressure Source


The Compushift uses both the throttle position and the MAP signal to set the clutch pack pressures,


TD5 MAP wiring


Connect the white/blue wire to engine ECU top red plug (C0158) pin 6, white/yellow wire

Connect the white/brown wire to ground


Tdci 2.2 MAP wiring


Connect the white/blue wire to engine ECU top plug (C0411) pin 28, blue/green wire

Connect the white/brown wire to ground


Tdci 2.4 MAP wiring


Connect the white/blue wire engine ECU bottom plug pin B1, blue/green wire

Connect the white/brown wire to ground


Miscellaneous Installation notes

We would advise disconnecting the transfer case high/low switch, otherwise the anti-stall gets very confused when in low range, anti- stall is not required with an automatic transmission.


Security Code feature

The new software now has a feature which can be used to write protect all parameters apart from two that are required for installation. These two are the ‘TPS calibration’ and ‘shift lever gear voltages’. This feature stops a customer accidentally resetting parameters unintentionally.


This feature will default to unlocked unless it has been supplied specifically for your application in which case it will be locked, if you wish to alter any of the locked parameters please contact us for the access code.

Customer Reviews

Average Rating: 5

Td5 130 auto conversion

Conversion went well, a big thanks to Dave as had a couple of little issues in the programming, went out of his way to help, sent a message Sunday night Oz time, and had a reply straight back and issue solved. The defender drives nicely with the auto, had one nightingale little issue was a flat spot in acceleration and this was the after market Cruze control, removed and problem sorted, tows extremely well, towed our 40ft header trailer 600klms with 3 tonne of steel to build a shed for our combine harvester, did the job with ease, left up north in the rain towing the same trailer empty, and the red Malle mud was no effort for the auto defender, very impressed.

John Munro :: Apr 13 2021, 08:41 AM

5 stars

Definitely a five star product

Luis Fernandes :: Oct 30 2018, 20:24 PM

Amazing product

I own a discovery2 Td5 Auto and a Defender 90 Td5 manual. Always wanted the Defender to drive as nice as the discovery2 and not like a truck, so I purchased from Ashcroft the torque converter conversion for the Td5 and the compushift 3 and I got myself a good second hand ZF4HP22. Everything was so easy to install and with the timeless assistance from Mike from HGS(compushift in California) and Dave from Ashcroft went like a breeze. The results are amazing the Defender now drives even better than the disco and with incredible adjustability. Thank you Dave and Mike and congratulations for the amazing product and for being real professionals.

Luis Fernandes :: Oct 26 2018, 22:13 PM

Compushift THREE

A New Generation Of Technology With Exciting Features.

Image4x4 :: Sep 21 2018, 07:43 AM

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