Electrics: Dashboard Dials and Digital Display Go Haywire

[TDanexeter]

Had my XC90 since Jan 2003.

6 months ago noticed water in both front footwells after heavy rain.
Dealer thought seals around windscreen may be leaking, but nothing found.
Thinking back, this coincided with "SRS Airbag Urgent" message in display.
Dealer found the codes could not be reset, but airbag electrics sound. To correct fault dealer recommended whole dashboard display unit to be replaced for £700+. Because of commitments this has yet to happen.

4 weeks ago entire digital display and dials (speed, rev counter, fuel and temp) started going haywire. They would abruptly go to zero, then to random setting and then after 5 minutes return to normal function, then happen 10 minutes later and so on. Digital displays go to 88888 ! Terrified when this all happened first time as I was driving back from France just after New Year.

No loss of power or function and all external and internal lights function normally.

Could it be something to do with the original problem with water in the foot wells somehow affecting the dashboard electrics?

Any advice gratefully received.

[Rockhopper]

Do you have a sunroof by any chance? If so get the drain channels checked for blockages / kinks as these have been know to cause water in footwells.

[Clan]

this could well be due to water in the footwell the foam under the carpet is a good 4 inches deep so by the time you notice it you have a a built in swimming pool and this will have damaged the amplifier and yaw sensor , it might help to unplug these and see if the display works properly as a first action .
Check the AC drain hose first , although only one side usualy gets wet if this is out of place .
Have you had a new windscreen ? Has it got VOVO on it ? fast fit windscreen fitters sometimes do a less than perfect job and they will eak . but original factory fitted screens very rarely leak ...

[chasbuddy]

My 04 had the same issue, basically it was found to be the vent pipe on the AC / rain water run out pipe. Apparently not fitted correctly at factory this is about the 20th Car I have heard of this happening to.

[RoscoMac]

My 54 xc90 also had windscreen seal leak. dealer repaired by sticking some black mastic around it. nice!

[jpbyes1]

Had the same problem

I think if you have the same problem that i did then you will find it to be a black plastic box located under the wiper motor. The top of the box warps with heat after time and then the water comes donw the screen onto the wiper motor and into the car through the hole in the center of the bocx.

A good tube of mastic and some cable ties did the job for me. Basic fix but it works.

Regards JP

[lurdenlaw]

I bought my XC90 new in January 2004 and over the last few months I've had exactly the same problem. Dashboard lights going all over the place, brake system failure warnings and airbag service required message. My garage (fully equipped Bosch specialist) has the same problem with a V70 which they service also a Ford Mondeo.

I had a double failure yesterday which may have been caused by water ingress but I've never seen any in the car. When I got to the garage they quickly reset the system but the owner told me that the V70 owner had found on the internet a power supply unit for the board at the back of the dashboard. apparently he was told by a Volvo main dealer that that is what is causing the problem but Volvo will NOT supply individual components under any circumstances (they would rather charge silly money for a complete new board)

Has anyone else heard of this?