Water in drivers footwell, and multiple problems

[edvardhole]

Hi!
Im one of the many guys with a Xc90 with water in footwell. The car had been stored outside for ca 3 months in winter climate, waiting for multiple repairs and parts. Now when starting up, the instruments work for ca 2 secs, then dead. Errors in display on engine and brakes. Gear indicator dead. Runs only in limp mode. Suspected wet cem, so reprogrammed new cem put in yesterday, no change. Noticed water sipping in from sunroof drain earlier. This is changed, but still its wet under pedals. Car is parked all the time. Vida show multiple errors on TCM, SAS and CEM. Where can water come from? Are there any earth points in the footwell, wet/corroded? Any other contacts or electronics, apart from CEM, typically injured by water intrusion?

[RickHaleParker]

Remove the trim from the inside of the A-pillar and look.

[crlande]

If they are anything like the 850 or S70 it may have the four drain tubes for cowl under the wipers and one for A/C drain. Drivers side bottom cowl tube ( which is under the fuse box, a hint? maybe?) may clog and soak the carpet.

[edvardhole]

Ok, thanks, will check. I really dont understand all the error codes. A corroded earth point somewhere?

[oragex]

Yaw sensor and audio amplifier under the front seats may also get corroded. Look inside the trunk where the battery cables go into panels, try to undo the cover of these and look inside. It's chasing a hidden issue, not easy to find and not much else than besides a wet CEM is known. Parking the car for long time without disconnecting the battery gets it drained and softwares can get corrupted. A rodent may also have got somewhere and chewed on wires. May also test the battery for being fully charged, and check all power cables, at the engine fuse panel, REM panel (trunk), look for corrosion at the DEM and PEM, check the wires to the connector at the radiator cooling fan.

[shiloh51933]

The drain tubes behind A-pillars are known issue for early model XC90, especially of there sitting unused for long periods. You have to resolve leak issues first, your just going to have same issues. The CEM is connected to all the other modules, if your CEM is fouled up then your going to have all kinds of intermittent problems. Have to resolve leak first.

[edvardhole]

Ok thanks guys. Leak from a pillars is fixed, footwell area and left side footwell wall is still wet when raining. Cem is new, no change. Battery charge and condition is top. Yaw rate sensor is under passenger seat I think, so this is probably not the problem, it is dry in this footwell. Will have to find water leak first yes. Maybe between hood and front window? Will probably store the car indoors in warm garage a couple of weeks. My suspiction is ground connections. Maybe fuse box connections? Are there any ground contacts in the footwell?

[shiloh51933]

I've seen leaves, pine needles and those squiggly things from oak trees clog up the hood cowl drains so bad that during a heavy rainstorm the water came inside through HVAC system. The vehicle was a 90's Nissan Maxima that had the ECU behind the head unit cluster positioned on the center hump...anyway the ECU got wet killing the whole car. We took it out and dried it then let it sit for few days. Those small pine needles and squiggly things always clogged everything up on vehicles.

[edvardhole]

Ok, thanks. I will have to find the leak, even if I fix the CEM-problems and everything works fine. So first leak, yes.

[RickHaleParker]

I will have to find the leak

Inspect the Windscreen seal at the top of the Windscreen. Sometimes the seal leaks, water passes and lands on the top side of the headliner then drains down the A pillar to the footwell.