2.5 Td Cruise Control, Retro fitting on 2.5 VSX

Hi All

As asked by Niek I have written up the method I have used to fit cruise control my VSX 2.5 TD's. I have to credit Paul Johnson of the Oxford Citroen Centre who advised me how to reto fit these cars. I tried using second hand bits but quickly realised this was a mistake as very few scrap cars have the parts and the one column lever I did obtain proved to be broken internally and caused me real trouble. When I decided to pay up for new bits I was surprised to find them both cheap and readily available.

Hope you find the information in the attached file usefull.

Regards

XMexc

Did like you said and it all works like a charm. Only thing still wrong is the light inside the dash button when the headlights are on.
Funny thing how the cruise needs to go full throttle when resuming the last speed on the highway.

Thanks!!

Hi Niek

Pleased your cruise add on worked. I had not noticed anything strange when returning to road speed but will try a few experiments to see what happens with mine. Regarding the button light problem it should light up behind the cruise arrow when the headlights are on. The orange light only comes on while the cruise button is switched on.

Regards

XMexc

I almost didn't buy my 2.5 because it didn't have cruise!!! I have checked and the wires are in place, switches will be on order on Monday morning.
Many Thanks,
Bigmixer

Hi Bixmixer

Glad to be of help. Hope all goes well with the mod. An update on the current switch prices might be useful for others. I have found cruise a superb addition when travelling long distances on quiet roads. Let us know how you get on.

Regards

XMexc

Switches fitted and working. Prices were only a few pence different from yours. I found that accurate drilling let me use a 16 mm hole in the shroud. As you say a great job for motorway work, I may be taking the XM to Greece next year and it would be invaluable.
Bigmixer
PS I checked my wife's Xantia HDI and the wires are present on it so I have ordered the switches, and will report when they are fitted.

Got the cruise swiches for the Xantia today and guess what? They don't fit the wiring on the car! The dealer has double checked and they are the right switches, in fact there is only one of on the parts list, as my first thought was that they had been wrongly supplied. Has anyone any ideas? My apologies as I know this is not an XM but maybe someone would know where to look for the answer- is there a Club Xantia Forum?
Bigmixer

Hi Xmexec and everyone else.

My latest V6 SEi 1993 model has criuse fitted as standard and its a BREEEEEEEZE

What is cruise like with a manual gearbox??? I find if I hold the control stalk up from 40mph the AUTO box kicks up a gear then back down and it NEVER wanders off the set speed up or down hills!!!

Puts a super smile on my face!

Regards
citroenxm

Hi Citroenxm

Have retro electronic cruise on the manual 2.5's and vaccum cruise on the 3.0 auto. They all perform identically. I particularly like the accelerate to overtake then just take your foot off again to settle to cruising speed. I find the accuracy so precise that you really notice that many people let the speed drop a few mph uphill then run just over the limit going down.

Regards

XMexc

how complex a job would it be to add cruise control on a V6 Sei Manual? It's a 1991 J reg.

Regards
David.

Hi David

The 2.5TD self help aint no use to you as it is all electronic and just needs fitting switches into an already existing wiring loom. My Mk2 V6 has the vac cruise fitted and it uses the same bits that were used for cruise on the Mk1's with cruise. If I had gone the way with the 2.5's originally suggested by my local Citroen dealers parts man I would have tried to fit a set of V6 vacuum bits to my 2.5 so somewhere I have a diagram and parts list for all the bits. I guess you need to find a scrap car and recover the bits.

Thinking about it you would need all the vac and mechanical bits. Also the switches, wiring loom and electronic vac system controller. All to fit to a car which has none of this kit or wiring already installed.

Sounds nearly as difficult as retro aircon to a 2.5 which has been my next years project for the last 3 years.

Sorry that I cant be more help.

Regards

XMexc

Followed the instructions and added the switched to my 2.5VSX, however it doesn't seem to work. Used new switches from Citroen.

When pressing the dash switch, it physically latches on but the light does not come on. I tried using it anyway and the stalk has no effect.

Anyone have any ideas what could be wrong? Anyone know which pins on the switches are what - I can then test it with a multimeter to check for dead switches (shouldn't be a problem) and track down the fault. Would this occur if there was a fault with the stalk?

One thing I did notice was that the dash switch has 5 pins on it, but there are only 4 witres on the plug (as described in the instructions).

Also the lights on that whole row of switches don't come on with the headlights - not a great problem, but if there is an obvious place to check for breaks then I may have a look. It is a M reg, so could it be a bulb in 1 switch (are the lights wired in series)?

For anyone interested - the prices are currently 28.97 and 17.74 for the switches - slightly up on the prices in the instructions, but not too much.

Hi Rowan

Try checking the fuses on the fuse board under the passenger dash. The back lighting to switches, the switch function on light and the function power supply can each be powered from a different fuse on an XM. On the cruise installation I had no power supply problems so did not need to identify any of the supply fuses, sorry. With an ABS fault I had on my V6 2 of the 3 fuses powering the ABS had failed. Took me nearly a year to find.
I think your lack of back lighting indicates a lack of feed from one of the fuses.
The failure of the Dash Switch to light up when switch suggests that the cruise control circuit is also not getting its supply.
If the fuses are not the problem then hopefully Noz can find a wiring diagram for the 2.5 cruise circuit so you can test with a meter for continuity.
I would not start rewiring until I was certain I had tried every other eventuality.

Regards

XMexc

My thoughts exactly.

I checked the switch with a multimeter, and it seems to be working correctly. In the off state, pin 1 is conntect to pin 3, but not pin 2. In the on state pin 1 is connected to pin 2 and not pin 3. Pin 3 is the one that is not connected to any wiring, so that all makes sense (as long as that is how the connector is wired of course).

I presume that the 'on' light is simply switched on from the power on pin 1 when the switch is on. That would all seem to backup your thoughts that it is probably a fuse assuming the wiring for the switch is as I am guessing.

I did a quick visual inspection of the fuse box earlier and did not see any that looked blown, but I have not checked them properly. I also haven't put the meter on pin 1 of the wiring to check for a voltage yet.

I guess the question is - is pin 1 the 'live' on the switch, and which fuse does it come from?

Finally had another look at this when I was taking other things appart. I had previously put a temporary supply to the dash switch, but it still doesn't work. I had checked the brake peddle switch and that was OK.

I thought I would look to see if I could get to the clutch switch - not a hope. but what I did see was that whilst the brake switch has the 3 wires, and works correctly, there are only 2 wires into the connector that the switch plugs into. i.e. the wire for the cruise is missing from the wiring loom

I guess that my car doesn't have all the wires in place correctly - hence there was no power to the dash switch (the wire was there on the connector, but not connected to anything further back I presume) and no connection to the brake peddle so the ECU thinks I am permanently braking.

Looks like it may not be possible on my XM, but I won't give up just yet. Does anyone have any idea where the connector onto the engine loom is? Is it with all the others by the fuse box, or is it somewhere else? According to the wiring diagrams it should be a black 9 way connector, but I can't see any black connectors onto the wiring through the bulkhead by the fuse box. If I could find it then I could try routing a connection from the brake peddly through to the connector (would be bypassing the clutch switch though) and see if it then works. Of course it may be that the connector is not there at all on mine.

For info I think my XM was one of the first 2.5s as it is summer 94 reg, so perhaps they had not fully sorted the wiring specs when they put it together.

Cheers,
Rowan.