Dead clocks

[zeekyboogydook]

Hi all,
Done a search to no avail for my specific problem
2001 1.9d berlingo van (y reg)
This morning the clocks have decided they don’t want to work anymore!
The digital screen bit is dead, the coolant temp, fuel gauge, Rev counter and speedo are dead, including the backlights.
The indicator lights in the clock, clicker thing aren’t working but the indicators work fine.
The oil pressure light I think and the battery light work fine, but the glow plug light does not illuminate, I think the plugs are working because it started fine.
Wipers and blowers etc all work fine it’s just dead clocks!
I’ve checked all the fuses and have followed the bsi reset procedure.
Any further advice would be very much appreciated!

[Sol]

You won't have a BSI from the year of vehicle - it's too early. Possibly either a wiring issue affecting the power or earth to the cluster or the cluster itself is faulty internally - it has a circuit board inside it with a controller for the functions. I don't have schematics for the M49 so unfortunately can't help with those. Not sure if the Haynes is available for that model.

It is possible there are fuses inside the cluster on the circuit board.

On that age of vehicle it's also likely a lot of the information is sent over separate wires for each part of the cluster so it must be something common to the whole thing. Worth pulling the unit out, to see if the main plug has come loose? Maybe from a pothole etc.

Some of the M49 guys may be along at some point with more (better) info for you.

[zeekyboogydook]

There’s my fuse box

There’s my corresponding fusebox layout.
I’ve heard mixed bags whether I have bsi or not!

[Sol]

The BSI was introduced to PSA vehicles in 2000 but likely only in flagship models to begin with like the high end saloon cars. It's a bit grey as to whether the early Berlingo had it. That picture you posted does look like a regular fuse-box.

Others who have worked extensively on the M49 will know for sure.

In any case, I'm certain the BSI reset would not fix a fully dead instrument cluster. If it reboots in a way that the software gets corrupted, it does crazy things like drop into service mode with the lights and wipers running constantly by themselves. Never heard of it causing a cluster to be dead completely, crazy icons lit but never all off / no rev counter or speedo etc.

[Sol]

Edit: I see that manual mentions a BSI fuse, is that a specific manual for the M49? If so then I guess you do have one. I've been told many times from others on here that it didn't but may have only referred to the 96-99 ones which makes sense.

[zeekyboogydook]

Yes it was the manual for this van itself.

This looks to be the bsi unit I have as it matches the bottom 6 fuses.
All of the instrument cluster fuses are good and are live when tested with a meter. I’m a sparky by trade, but this multiplex stuff is a bit deep for me!

[oilyrag]

It is not too bad a job to get the instrument cluster out - air vents screws, radio & carrier out, indicator/lights/wiper  'shell' removed. Needs suitable Torx.  There are a couple of plugs on the back of the cluster - I don't recall seeing any sign of fuses, but then again, I wasn't looking for them at the time. Takes about 15/20 mins to get the whole assembly out.  
Good luck!

[zeekyboogydook]

Yep had the back out and it all looks fine. Taking it to the local Citroen specialist, they’ll be able to scan it and test the bsi/clocks properly and go from there.

[Gryffindor]

I had earlier guessed that the BSI system came in with the M59 because both came in at roughly the same time - but it was only a guess and is now proved wrong - sorry.

Just had another look at the H manual available elsewhere on this forum as a PDF and it covers all models 1996-2005 (it was printed in 2006 so may also cover later M59s) - all engines except 1.8 petrol (i.e. it covers all diesels and all other petrols).

One thing I noticed in passing (on my way to but not quite at the wiring diags) is that the airbag system was changed in Sept 2002. At a glance the poking screwdrivers into three holes trick only applies after that date, but I didn't allow myself to get properly distracted by this.

Is Sept 2002 when the M59 appeared?

An overview and removal guide to the BSI appears on page 12:18 (pdf page 323), making no reference to differences between models, so this alone SEEMS to suggest that it is even found in 1996 models?

The wiring diags begin on the next page. Because of the above note on the BSI I didn't go through them.

[Gryffindor]

Trying to understand the symptoms you list on the assumption that you do have BSI & multiplexing.

Almost all the issues seem to be with displaying of parameters rather than their actual operation - but see lower down.

A multiplexed cluster is really just the end in a chain; another bit is the MFD (multi function display) which sits above the radio - is this what you mean by "digital screen bit"? If so, then the problem could be further down the chain to a common point between both that and the cluster, i.e. the loom between them and the BSI and/or the radio (which is also part of that multiplexed bus loom).

This is the lower down bit. If by backlights you mean the rear light clusters on the back of your car, then that's not a driver display item and such a fault doesn't fit into the pattern of your other faults. Or do you mean the backlights of instrument displays?

What clock's indicator lights don't work - the MFD? Can't remember offhand but its lights (2 or 3 festoon bulbs) may have their own 12v supply independent of the bus loom, or they may get it from the loom's +v wire. Which is the case may help drill down a bit more. Could a fuse have blown somewhere - dd you check ALL of them even those hidden under where was it - the batt tray? Never been there myself, just half-remembering other posts.

The batt light working is curious to me (as a non-mech/leccy) - that suggests that t is operated more directly from the charging circuit than via the BSI as with most other indicating lamps. Can anyone more knowledgeable deduce anything from this?

I won't try to draw any half-baked conclusions but will leave this as a few notes on the symptoms. Hopefully a proper surgeon will enter the theatre and know what to start cutting open after he reads them.