AWD and DSC malfunction, Engine malfunction, DBC malfunction

[JamnX5]

Thanks. The battery was replaced 6 months ago. The dealer states it could be wiring harness (cable). They are repairing X5 with the same issue to confirm resolution. My baby will be next in line for the repair.

[crazyivan]

Feel free to skip to the solution down below. Otherwise, here's the full story...

Back in december I experienced identical symptoms on my 2008 X5 4.8i (44k miles): dashboard lit up like a xmas tree and nav screen displayed AWD, DSC, Engine, Brake, etc. malfunctions. At the same time the car would go into limp mode (basically not drivable) and I would have to pull over, kill the engine and restart the engine to continue driving. Some of the lights/malfunctions would stay ON but the car was drivable.

I checked the battery and found that it was reading less than 12V on my meter. I put it on the trusty Battery Tender for approximately 24 hours. Checked the voltage again, it was at 12V exactly. Too low. I did some googling and came across posts that said a low battery could cause the symptoms I'm seeing, so knowing that a new batter has to be registered with the onboard computer I took my car to a local BMW independent to replace the battery. They agreed with my diagnosis and $300+ later (with labor) I'm experiencing the same symptoms.

The same independent used a very expensive Autologic diagnostics device to simply clear the codes and sent me on my way. A few minutes I came back so they can read the newly generated codes (symptoms came back just a few miles after leaving the place). They found some Throttle Body related codes. His initial conclusion was to replace the Throttle Body motor (as he called it).

SOLUTION: My dad and I got together, disconnected the air intake from the throttle body (very easy to do) and found that the throttle plate and the inside of the throttle body was caked with dirt. We concluded that the throttle plate could easily be sticking and causing the onboard computer to freak out throw the car into limp mode. I bought some throttle body cleaner. Dad turned the ignition on and pushed down and released the gas pedal. This opened the throttle plate for a few seconds which allowed me to reach in do a bit of cleaning. Repeated this process several times until the plate and the body was free of dirt, squeaky clean. 1500 miles later the symptoms have not returned (spit three times and knock on wood).

Just thought I'd share since this seems to be a very common problem out there.

[JamnX5]

Thanks for posting. Two weeks and counting as of today. Car still in the shop. Dealer states BMWNA recommend replacing a wiring harness. Another X5 was in before me and they are getting the fix first. They are testing that vehicle to confirm fix. They will work on mine shortly. Maybe I should suggest this fix? I would hate to tell them how to fix vehicle

[seattle]

Sometimes you have to tell them how to fix. Hard to believe, but there's a lot of guess work there in the shop. They just throw parts at the problem in hope it goes away.

[JamnX5]

I agree. Throwing parts at the problem is the norm. Maybe they should call the main office more often. However, that would make the service dept look incompetent.

Shop forearm should have an idea today on the repairs.

[eurogreek1]

What year is your x? If it's a 2007, I might know what the problem is. I had mine at the shop for over 10 days chasing ghosts.

[seattle]

Perhaps pay a visit and talk to the shop foreman. You have a complete right to see what's being done to your vehicle. Just nicely ask to take a look, then mention that your "close friend" had exact same symptoms on their vehicle, and perhaps they can check throttle body.

[JamnX5]

I have 09 4.8. The SA states that have the approval to replace the wiring harness. The throttle body/wire harness has been replaced. Battery is brand new. I guess it could be alternator, but you would think they would have ruled it out. Another X5 was in for the same thing and BMWNA suggested the wiring harness replacement. The other vehicle is ok now. I should have the vehicle back by Tuesday. I keep you all posted.

[ard]

Originally Posted by JamnX5

the wiring harness.

Which wiring harness?!?!

You posted earlier about a harness replacement.... but others have posted the harness fixed their issue. Will this be a second and different harness they are replacing?

When they call with info, dont feel intimidated - ASK 'what is the part number, what is the SIB'. When the jerkwad SA says "I dont have that in front of me" say "No worries, I'll wait".

[JamnX5]

Good point ard. I think he said the main wiring harness. Not sure... The throttle wire harness/body was replaced a couple of weeks ago. The SA stated they had the approval from BMWNA to replace. This was an odd statement?? My vehicle is still under factory extended CPO warranty. I'll post Tuesday when I get the vehicle back..I hope.