Retrofitting touch screen sat nav controls

After much planning and hard work, this is the guide for retrofitting the touch screen controls to an X-Type. It is my understanding that the process will be largely similar for the S-Type and later XJ models, albeit the wiring will take a different route. The photos are copyright P Clements and are used with permission.

Introduction

Fitting the touch screen controls are a commonly requested modification on these forums that is often quickly dismissed as being too expensive to be worthwhile. Hopefully this thread will proove that it need not be. This retrofit was completed for approx £500 and was a relatively straightforward task. Below is the before photo, and above is the after photo.

Firstly the disclaimer: if you plan to do this remember that you risk damaging your car if you get it wrong. I will not be held responsible if this happens, although I will answer any questions and help out where I can.

Now the unfortunate bit: the target car will need to have the automatic climate control option t be upgraded. That is the system with the large LCD panel as shown above. If you have the manual dials then it really won't be cost effective to upgrade because you will be changing your climate control system as well.

If everything so far is ok though, then you will need the following:

- The touch screen, with the same spec as your windscreen (heated or normal, indicated by a separate 'F' heater button above te rear screen heater button.
- The sat nav DVD unit for the boot
- The remote climate control unit (more details below)
- An upgrade harness
- A TomTom GPS antenna/mouse
- A single optical link for the boot (daisy chained into your existing lead)

The touch screens and DVD units pop up on eBay regularly for an average selling price of £200 and £150 respectively. Shop around though and you can get them much cheaper. The GPS antenna shown below is the Jaguar one, but any TomTom one will do and they are much more common.

The remote climate control units are rarer on eBay but any car being scraped that had the touch screen controls will have one. It is attached to the right hand side of the heater/evaporator unit behind the dash. It can be accessed easily by removing the carpet above the RH foot well and reaching up. New from Jaguar these cost around £400, but the one below was sourced for £70 so shop around and play the breakers off one another if you can.

As with previous projects, the harness shown below was custom made by myself. Basically it consists of a shielded cable for the video signals and a bunch of straight and twisted cables to carry control signals and network commands between the front and rear of the car. The connectors are either donored from radio adapter leaders (the telemute kind) or crimped and insulated loose ends. The harness is complately plug-and-play with no cutting of any existing cables required to make it easy to fit and allow for the system to be swapped back in the future.

Fitting Guide

The process goes like this:
1) Remove the left hand floor trim pieces, boot/trunk carpet and the rear seats to route the cable from the front to back in the existing cable runs.
2) Run the harness up behind the hood/bonnet release lever trim and underneath the glove box (or steering column in LHD cars)
3) Swap out centre console panels for the touch screen
4) Install the sat nav DVD unit in the equipment rack in the boot/trunk
5) Dasiy chain the new optical link into the link lead, and connect all cables/leads
6) Fit the remote climate control unit to the RH side of the heater/evaporator unit (accessed via the bottom)
7) Turn on car and play with the new controls!

Remove the left hand floor trim pieces, boot/trunk carpet and the rear seats to route the cable from the front to back in the existing cable runs.

I wont cover removing the boot carpet as it is obvious when you look at it. The rear seat cushion pulls up firmly at either front corner and then lifts out. The wings on the clips normally break off, but it will still hold firm without them. The seat back is held in place by the two bolts that become visible when the cushion is removed. Undo them both and lift the seat back off the hanging hooks.

The floor trim down the left hand side of the cabin is tricky to remove the first time, but so long as you unclip the front edges of the trim where it meets the lower B and A pillar trims it should be straightforward. Take your time and feel for the stress points with your fingers - those are where the clips are. If you do damage them beyond reuse then the good news is they are very cheap to replace new from a dealer.

This is the front cable run that is underneath the plastic trim:

And this is the rear:

The upgrade harness should be tucked underneath the inside edge (that is where the factory harness would fit).

Run the harness up behind the hood/bonnet release lever trim and underneath the glove box (or steering column in LHD cars)

The lower A panel trim / cowl trim is a pain to remove. Notice in the photo below (the removed trim is on the right) that there are two tongues that clip behnd the carpet at the rear, and there are two metal push clips that fit into the front edge of the frame (one of the clip holes can be seen next to the bonnet/hood release lever). Route the harness up behind this and use common sense to run it underneath the glove box (or steering column) to the centre console.

Swap out centre console panels for the touch screen

The centre console is easy to remove. Open the ashtray and with your fingers under the front edge of the gear stick or J-gate trim pull firmly upwards. There are two clips at the front and the back. Once that is out remove the exposed screws holding the ash tray in and carefully slide it out. There are two T star headed screws behind that holding the base of the console electronics in place. At the top there are two more of those screws which are hidden behind the hazard switch trim. Gently remove the trim by hooking a small flat screwdriver under a pointed corner and prying it up. (Don't worry, you can't break it through force, the clips are sprung plastic.)

Remove all the connectors, and detach the climate control panel and telephone buttons from your CD player or tape deck. The two connectors from the climate control panel need to be poked through the hole on the RH side so they fall behind the steering column (glove box on LHD vehicles), ready to plug straight into the remote unit when fitted.

Mount the CD player or tape deck to the touch screen frame, and swap over your hazard switch if needed. I couldn't find a mating connector for the touch screen so my harness is terminated with insulated ends that need to be matched up to the correct pins. The stereo connector though is straight plug-and-play. (Note: in the future I will supply blanks for the other pins on the screen connector to allow them to be stacked and taped after fitting to avoid them being pulled out when refitting.)

Now plug the new harness into the stereo head unit and connect the other end into the original stereo harness. Carefully slide the equipment back into place and replace all the screws and trim.

Just in case you forget, the green heated seat connector goes on the left:

Install the sat nav DVD unit in the equipment rack in the boot/trunk

The harness routes into the back via the existing cable trays. You will need to remove the existing equipment rack to gain enough access to fit it.

Screw the DVD unit to the rack while it is detached and then connect the harness to the DVD unit (shown unfitted below). One of the connectors is plug-and-play, the other is loose ends as with the screen. Once connected up use tape or a cable tie to hld the cables together to prevent them being knocked out when refitting the rack.

Dasiy chain the new optical link into the link lead, and connect all cables/leads

The DVD unit sits on the optical D2B network with the stereo head unit, and another other devices such as the CD changer, telephone, voice controls, etc. Each network has a custom optical link lead that connects to each device in a specific order. Get the other wrong and nothing will work! Using the diagrams, carefully disasemble and reassemble the new link lead in the correct sequence, and connect it up. (Note, the factory link lead for the DVD unit has a right angle connector, but the more common straight out one will work just fine.)

Plug the GPS antenna into the rear of the DVD unit, and route the cable along the bodywork and attach it inside the parcel shelf by poking it through one of the holes in the top of the boot/trunk. Make sure it is fixed in place with tape or velcro so it doesn't move around. Then refit the equipment rack and all the carpet.

Fit the remote climate control unit to the RH side of the heater/evaporator unit (accessed via the bottom)

Remove the carpet above the RH foot well, and on your back with your head painfully positioned up in the gap slot the remote climate control unit into the existing mounting. Fix it in place with a single screw where shown. Plug it into the original climate control harness you rerouted earlier.

Turn on car and play with the new controls!

It is worth noting that the upgrade harness gives you one advantage over the factory system - you get an inline connector that allows you to plug in any RGB video switch and put your own video onto the touch screen, shown below.