Long time lurker. Somewhat excited to try my first repair on this car.
Here are the issues:
initially there would be a flash of an error so fast I couldn't see it, and the steering wheel would be a little bit harder to turn like the power steering was weakened.
Now, I will sometimes get flickers of various faults that sometimes go away. Usually they stay on, and the tach will go dead, the speedometer will go dead, steering will be harder again, dcs fault, gearbox fault, parking break fault, abd (I think) fault, tpms fault, battery not charging, and one other I cant remember.
It's not always the full catalogue of the above. Maybe 60% of the time. The parking brake fault, gearbox fault, dcs, and tpms are the usual suspects almost every time.

I'm aware the first fix is the battery which I replaced. I cannot find any reoccurring event to cause this as sometimes it will happen at idle, sometimes not at all.

Any thoughts?

 

2013 XF btw

 

 

Yep - if you're sure the battery's good I'd be checking the grounding cables - especially the engine grounding cable - this bolts onto the rear bottom of the engine block, actually on one of the starter motor bolts that goes through the bellhousing. It's easy to unbolt and just make sure it's not rusty - if it is, clean it up with a wire brush, and grease it if you live in the rust belt.

If the cables all look good then I think my next port of call would be the alternator - check the cables to it, and also check you're getting a continuously good voltage from it. You may want to think about buying one of those bluetooth OBDII readers with an app that shows the voltage level, then the next time you see the errors going crazy, see if the voltage fluctuates. You'll also be able to read any codes thrown and act accordingly.

 

I'll give it a look! Is there a diagram showing the location of the grounds?

 

Facelift X250 suffers from water in the fusebox caused by faulty washer bottle pump, lots of info about this fault on the net!

 

I will check this as well thank you!

 

I didnt see any water now, but since you mentioned it my wife did leave the trunk open over night when it rained once. Could that be the start of the issue? I never put two and two together bc I didnt realize there was a fuse box in the trunk so I'm unsure of the timeline. Could this be the root of it and if so, what's my COA?

 

Trunk open during a rainy night could well cause issues if the rear fuse box got wet - there's fuses for quite a few fundamental systems running through there, and from memory not very much other than the trunk lid and a thin piece of trunk lining trim protecting it from the elements. I'd take a look a it and see if you can see any obvious signs of water - pull a couple of fuses out and take a look at the terminals - see if there's any powdery residue or any other sign of water ingress. If there is, I'd disconnect the battery, take a good photo of the fuse box so you can put all the fuses back where they're supposed to be, then pull them all out and clean the fuse box as well as the fuses with a good electrical cleaning spray. Also check the contact of the ground lead for the battery.

 

It's the fusebox in the footwell that suffers from the washerpump issue!

 

I pulled some of the fuses and the ends looked somewhat scorched/discolored. Normal?

There was some white powder behind the RH footwell fuse box. Do I completely remove the fuse box? Do I need to replace all the fuses down there? I will document for a how-to since it's a known issue, but there isnt one out there yet to point people to.

 

Not really, although so long as they measure good on a continuity test with a multimeter I don't see why they can't be reused. However, I'd say that combined with

this doesn't sound right and definitely sounds like it could be the washer pump issue as others have mentioned. Personally I'd be trying to remove the whole fuse box and all the fuses to give everything a real good cleaning (with battery disconnected throughout!). Also drain the washer tank (you may just need to run the washers for a while to do this ) to find the source of the leak and stop it re-occuring (unless there's a different fix for this documented elsewhere, have a search on the forums).

 

Just saw this link posted in this other thread - definitely sounds related and worth checking.

 

I got a code reader and received the following codes when the car electronically shat itself today. 8 pages of the same codes repeating.
U0100 - signals between the electronic control module (ECM) or the powertrain control module (PCM) and a particular module have been lost. There could also be a problem with the CAN bus wiring disrupting communications.
U0300 - incompatible software levels within the Powertrain Control Module (PCM) that control the Electronic Throttle Control (ETC) system. The ETC system uses multiple microprocessors within the PCM, each having its own software level and function.
U0001 - canbus

I've read it could be a foot brake switch, fuse box as mentioned above, or the the gearbox module needs to be reprogrammed. Any insight? I'm cleaning the fuses and box now just to be safe and its something I can do myself. Should I replace the foot brake switch next or send to the dealer?

 

bump for code question

 

@3kgtjunkie - Which fuse box are you looking at? There are 3 of them - engine, inside car and trunk.
If you didn't check yet, look at the one inside car, will be on the right side, under the dash, just before the door. That's where all my issues are coming from - and that included some Powertrain faulty codes. Unplug the connectors and see what shape they are in.

 

I looked at the one you're referring to, but I'm not sure what I'm looking at or for. It seems like dusty in there? But I havent seen corrosion like what you'd see on a battery... should I pull the whole fuse box out?

 

If it looks clean, then I guess maybe you have something else... for me it was looking like this - cleaned it now and replaced the washer pump:

 

That particular socket is empty for me as well. Did you pull all the fuses too?

 

Any updates on this? My car has literally done the exact same thing to the T! had the auxiliary battery replaced, but still gives multiple fault codes. Was there ever a resolution to this problem?