LCD display dead

Bit of a long shot - but thought I'd ask in case anyone has any ideas.

The instruments on my WR250R have died - the LCD display is back-lit, but no graphics are displayed.

The warning lights (neutral, fuel, indicators etc) all still work fine, but the LCD portion refuses to start up.

Everything was working fine, then one day I was about to change the oil so switched the ignition on to note the miles, and the display was down.
I pressed one of the buttons on the dash, and it came back up, so I just shrugged and noted the miles.

Next time I turned the ignition on, the dash was dead again, and has remained that way ever since.

I checked, dried, cleaned, and reconnected all the connectors around the headstock and back down the loom to where it disappears under the tank.
I also put the clocks in a warm place inside the house for a week, in case there was any condensation from when I washed the bike last.
All of the fuses are good.

Nothing works, and we've had several weeks of warm dry weather here, so I doubt it could be water related.
The bike starts and runs fine, but the instruments are just blank.

BTW - I fitted a SpeedoDRD a few weeks before, but the bike was working fine after that.
I did try removing it from the wiring loom but that didn't make any difference to the clocks; they stayed dead.

So, next step is going to be to split the instrument cluster and look for a problem on the circuit board.
Before I do that, I wondered if anyone has any ideas please?

Based on what I'm reading, I'm inclined to think there is something more going on but, please double check the backup fuse. It will take out the digits on the display and the backlight will still be working. It's the 3rd 7.5A fuse counting from left to right in the fuse block that's inside the left side cowling. Fuse 3 in the owners maual.

Very simple circuit as the wire from the 7.5A fuse is only connected to the display.

Thanks Heoz,

I'll take another look - already checked the fuses - but maybe I missed it.
In fact for a few pence, I'll change it anyway I think

Update:

Fuse looked OK - but swapped it out for a known good one anyhow - no difference with display

Any other ideas please?

If you're handy with a meter, check for voltage (12V) on the red/green wire that goes into the display. It's unswitched so you wouldn't even need to turn the key. You can turn it if you desire, but it should give the same reading regardless of the key position.

The power circuit for the backup fuse: power from the battery to the fuse block, through the backup fuse to the red/green wire on the back of the fuse block and that wire connects into the display.

Not much to go on after the power goes into the display as the schematic just shows an empty box.

If you end up splitting the display and you have the means, I'd be interested in seeing a picture of what's inside.

Thanks - will give that a try and let you know the outcome.

Update:

Checked power supply with meter - all good there - so must be something inside the instrument box.

Split it in half using a dremmel and took a good look inside.

Found several possible causes of the problem;
1 - The permanent live pin from connector block to board had a lot of corrosion (I initially thought it might have gone right through).
2 - A number of other parts of the board had some light corrosion
3 - One of the larger components on the back (which seemed to be driving the display) had a corroded joint.

I cleaned everything up using a brush and magnifying glass, and got the display to half work (random digits coming up in different places so long as I pressed the glass down) but couldn't get it to work properly.

Conclusion: Obviously there had been some water ingress at some point before I bought the bike, and it had damaged the circuit board.
Maybe the failure was caused by corrosion on the board or possible component failure, but whatever it was has put it beyond home repair.

Will live with it for now, and replace the whole lot with a Trail Tech Vector dash combination sometime when I feel the inclination.

Thanks for trying to help

SPL wrote:

Update:

Checked power supply with meter - all good there - so must be something inside the instrument box.

Split it in half using a dremmel and took a good look inside.

Found several possible causes of the problem;
1 - The permanent live pin from connector block to board had a lot of corrosion (I initially thought it might have gone right through).
2 - A number of other parts of the board had some light corrosion
3 - One of the larger components on the back (which seemed to be driving the display) had a corroded joint.

I cleaned everything up using a brush and magnifying glass, and got the display to half work (random digits coming up in different places so long as I pressed the glass down) but couldn't get it to work properly.

Conclusion: Obviously there had been some water ingress at some point before I bought the bike, and it had damaged the circuit board.
Maybe the failure was caused by corrosion on the board or possible component failure, but whatever it was has put it beyond home repair.

Will live with it for now, and replace the whole lot with a Trail Tech Vector dash combination sometime when I feel the inclination.

Thanks for trying to help

Good Work! Sorry you are still on the hook for a new head.

So......... as you were dismantling the unit did you get any idea where water is able to make it's way in so others can do preventative Maint?

There wasn't really any obvious cause of the water getting in.

The two halves of the instruments seemed to be really well stuck together, with a tongue and groove style overlap (it took quite a bit of dremmel work to get them apart! ).

One thing that was noticeable, is that there was a zip tie around the wiring boot to make sure it stayed in place on the back of the clock housing.
Maybe the previous owner had a problem with this working loose and letting water in - but who knows?

I would guess it wouldn't do any harm to put a small bead of silicone around the join between the top and bottom of the instrument housing, just in case there are any gaps in the seal.
The zip tie on the rubber boot is also quite a good idea, and I would be tempted to put some silicone around the mounting point too, before fitting the boot and the zip tie.
The only other thing I would suggest is maybe a smear of silicone around the wiring harness where it enters the base of boot too?

All of the above is not much more than guess work - because I couldn't see any obvious reason why I had water damage in there.
But as it had clearly happened a while back (before I bought the bike) I have no idea if at some point the boot was loose.

If it wasn't sealed right, and the bike was ridden through water (or jet washed with too much enthusiasm) I think that would have been enough...