Wanted : Series 2 clocks for a TCT manual

[robert_e_smart]

Hi Folks,

I'm after some clocks for a Series 2 TCT Manual.

The TCT in question always reads 55mph at present (and the counter doesn't work when it does this as well)! It used to be an intermittant fault, and a good thump of the dash would resume normal serivce. However this has stopped curing the problem. I have taken the clocks out and re-soldered the wiring connector onto the PCB. This helped momentarily, but normal 55mph service was resumed.

Am I off the mark here? Is it likely to be the sender on the gearbox?

Thanks

Robert

[Regdorpten]

Bit odd that it sticks at 55mph. Usually a sender problem means it either doesn't work at all or flickers the correct speed on and off. That was the problem with mine and a new sender sorted it. It's an easy job but you have to get under the car to do it.

Matt

[andmcit]

My first 2.5 does this and a good thump fixes it most of the time.
It was a similar issue at 50 on a Xantia my father uses and as you
say resoldering the speedo fixed it.

I guess it could be the sender but it would be all or nothing surely?
Can you not try a spare set of clocks even if they're calibrated
differently for the car in question to prove one end or the other?
Guess it could be an iffy cable varying physical resistance under
varying temperatures?

Andrew

[robert_e_smart]

I don't think its a temperature thing, as soon as the car moves, it shoots up, and only comes down to rest when the car stops.

I agree with the sender, it would be all or nothing. And thumping the dash wouldn't cure the sender of an intermittant fault.

I was thinking of sticking in some spare clocks too, but wanted to see what suggestions would be made as well. I'll try clocks if I remember to bring them over the next time I'm at my Pal's house.

[xmexclusive]

Hi Robert

Fixed speed value sounds like a false feed.
There is a connection (white plug and socket) in the speedo feed.
Same plug and wiring as on the sender.
It is found just under the LHM tank.
I have been meaning to set up a spare sender and a little 12v DC motor so I can feed a test signal into the speedo.
Got the spec for the output signals somewhere so must try to look them out.
They came courtesy of a chinese supplier who offered me 100 senders for $75 posted to uk.
Sadly I was only looking for a single one at the time.
Citroen's price for one was more than that so they did not get my business either.
Plenty of spare clocks here if you want a set to try, any preference on clock mileage to be close to existing?

John

[robert_e_smart]

The plot thickens. It wouldn't be a XM if it wasn't a wiring fault .

I'll try some of the diesel clocks I have here to try and eliminate the clocks. Out of curiosity is the speedo pickup the same on an auto as on a manual box?

If it is clocks, circa 80-90k would be in keeping with the cars mileage.

[Dieselman]

I'll try some of the diesel clocks I have here to try and eliminate the clocks. Out of curiosity is the speedo pickup the same on an auto as on a manual box?

I thought he speedo pickup was the same, if not it will be the number of teeth on the gear but will still give a half sensible reading for testing.

[xmexclusive]

The speedo drive box is common across all Mk2 XM's and many other PSA cars.
The drive cog that suits a particular model is a push fit in the drive box.
These drive cogs are colour coded but when I tried to order one the Citroen dealer there were 18 different ones listed but he was not able to identify one to a particular model. He suggested that I took the old one out and brought it in for identification.
I wanted the complete assembly to avoid effectively doing the job twice.
Over the years the drive box has evolved. The first version on early Mk1 XM had just a mechanical cable drive socket.
Then they replaced it with a dual function one, mechanical cable drive and electrical connector.
On these the mechanical drive socket usually points upward when fitted.
To start with that socket was left empty to collect water, which it did very well.
Early Mk2 's often have these fitted. The next stage was a rubber bung shaped like a cable end.
The water often still got in. Some garages filled the socket with silicone adhesive. This did better.
The final version of the drive just had the electrical connection.

John

[Dieselman]

Over the years the drive box has evolved. The first version on early Mk1 XM had just a mechanical cable drive socket.
Then they replaced it with a dual function one, mechanical cable drive and electrical connector.
On these the mechanical drive socket usually points upward when fitted.
To start with that socket was left empty to collect water, which it did very well.
Early Mk2 's often have these fitted. The next stage was a rubber bung shaped like a cable end.
The water often still got in. Some garages filled the socket with silicone adhesive. This did better.
The final version of the drive just had the electrical connection.

John

In case anyone is wondering why the changes ,the ones with cable and electrical connector are required for cruise control, then later the whole dash went to electric anyway.