Instrument failure ??

[Tubthumper]

I have a 2000 (X reg), 101, 000 miles, 2.0HDI estate , which has developed a couple of issues. First was the temp guage that began falling back to zero, and now only works correctly for 50% of the time. Secondly, the speedo also falls back to zero, not at the same time as the temp guage, and works for 75% of the time. I don't notice a drop in power when the speedo stops working, but the mileometer also freezes, and the mpg readout reads a blank. I have unplugged the speedo plug at the gearbox, and cleaned it, and have also removed the clocks, to check for a loose plug, which didn't appear to be so. I have also unplugged and cleaned the green plug from the temp sensor, but to no avail. Any ideas ??

[Captain Jack]

Possibly BSI playing up or even water under the carpet, which has a massive multi-pin plug. This seems vulnerable to moisture penetration.

However, I would first take the clocks back out and run a soldering iron over all of the joints just in case some are dry.

[Tubthumper]

Thanks for the reply. I have checked the plugs etc under the carpet in the passenger footwell, which all looked to be secure, and the carpets are all dry.

[TheSongRemainsTheSame]

I've done a couple with soldering, its quite a lot easier than it sounds. I just heat the pins so the solder resets and then add some more to be sure. You just do the big ones that actually connects to the gauges.

Also isnt there a black box of sorts behind the glove box on the hdi? Is this just for speed or can it cause other problems as well? Might want to look that up:)

[Captain Jack]

Also isnt there a black box of sorts behind the glove box on the hdi? Is this just for speed or can it cause other problems as well? Might want to look that up:)

It's the BSI, which can sometimes go wonky. And not just on HDI but all D9 cars (1999 onwards).

[steve_earwig]

I reckon he means the transponder box which did the speedo on ML5T-equiped 406s (2.1td, turbo & V6, not sure if it went into D8 HDis though). All handled by the BSI on later cars as CJ says.

Nobody mentioned what the mpg display did when the transponder was playing up before but if it goes blank then I reckon it's unlikely to be the clocks. What did the temperature gauge do when you shorted the connector for the sensor to ground?

[Tubthumper]

I reckon he means the transponder box which did the speedo on ML5T-equiped 406s (2.1td, turbo & V6, not sure if it went into D8 HDis though). All handled by the BSI on later cars as CJ says.

Nobody mentioned what the mpg display did when the transponder was playing up before but if it goes blank then I reckon it's unlikely to be the clocks. What did the temperature gauge do when you shorted the connector for the sensor to ground?

Has anybody got a pic or diagram of what the BSI unit looks like, and how to get at it, as I've checked my Haynes manual, and it does'nt mention anything about a BSI at all ?
The fact that the mpg display goes blank, and both the mileometer on the computer and the clocks stops increasing when the speedo drops to zero did make me wonder whether the fault lay elsewhere, but I guess the comp could take it's feed from the clocks ??
Rather stupidly, I didn't run the car with the temp sensor unplugged, but I'll have another go sometime over the weekend.

Apart from these silly issues ( well, apart from the radio not turning off occasionally when the keys are taken out ! ) the car suits my needs perfectly, so I hope I can sort them sooner rather than later .

[lozz]

Bsi is located behind the fusebox,

Becarefull with it if you removing it


http://autodiagnos.com/fileadmin/assets ... mplete.pdf

[Tubthumper]

Cheers lozz , I was looking behind the glovebox

[lozz]

Ah rite ,


Have you not tried: re booting the bsi?

Might not work but you might get lucky,


http://www.bba-reman.com/content.aspx?c ... ot_process

[Tubthumper]

I think that a reboot has got to be worth a shot. Thanks again for the info.

[Tubthumper]

Well, I tried the reboot this morning, but alas, to no avail

When it stops raining, I'll have a look at the BSI , to see whether there are any loose contacts there.

[Doggy]

If anyone near you has PP2000, they can test all of the clocks with the 'test actuators' function, (which makes all of them dance from min to max reading & back for a short period, so you can see if they work OK).

Guess I'm not a million miles away, (NN17), but there may be somebody nearer.

[Tubthumper]

Thanks Doggy, I've got a really good garage near me, in Tring , so I think the time has come to give the car over to them, as they've got all the diag equipment. The omly hope is that the intermitant faults show up when being tested !

[mattyg]

could it be the gearbox speed sensor on the gearbox? my car had the same fault used to drop to zero changed it its been great ever since.

matt