[08tt335]

I just bought my 335i last Tuesday and so far it's been a nightmare. After 24 hours of driving the car it started to spazz out on me. First the yellow brake light comes on, then the abs and multiple other lights on the dash. The only light I haven't seen pop up is the check engine light. The wipers go on and off on their own, the windows and power seats lose function and the interior lights go on and off on their own. Eventually the car goes into limp mode and overheats. Also, the turn signals work when they want to. I notice that after the car sits overnight I get in and it runs perfectly for about 10 minutes before the problems start to occur. The dealer is trying to work with me on the issues. They have had the car since last thursday and they have replaced the water pump, thermostat, radiator and upper hose. This hasn't fixed anything at all. They gave it back to me assuring that it drives fine mechanically but it still has an electrical issue. But even after replacing those parts it still overheats. I bought the car with 74,000 miles on it and I haven't bought the extended warranty through the dealer because its third party and all they can do is reumburse me. I love the car but as of now its a love/hate relationship with this beautiful machine.

[galahad05]

The overheating sounds like the radiator fan and/or electric water pump aren't being run correctly.

I assume this car has had the Battery IBS recall done on it? Also, how old is the battery?

[Abax335]

Sounds like a k-can issue with the wipers and instrument cluster going in and out.

That can get messy very quickly. I've had cars completely gutted for finding those issues. Is there is any after market equipment?

[08tt335]

As far as I know the dealership changed the battery and everything is stock. I had a feeling that one of the previous owners installed a jb4 or similar and then returned it to stock before trade-in.

[Gohan335i7]

Sounds like you may have bought a 335 with a ton of problems. However, I do have some advice. A. Find a highly reputable Indy shop because taking your car to the stealership is just a bad idea. Anywhere that treats you like a number and not a car enthusiast is not worth going to. That's 1/3 of your problems gone. B. Buy an extended warranty from anyone except BMW so that you can make monthly payments. . C. Check to see if your turbos have been replaced because if they haven't then you can replace them under the BMWNA turbo warranty that lasts until 82,000 miles I believe. D. look up Mike Millers BMW lifetime maintenance schedule so that you can keep up to date with everything your car needs annually. Hope this helps. Good Luck with your 335i -Gohan335iE90

[msjulesy]

Originally Posted by 08tt335

As far as I know the dealership changed the battery and everything is stock. I had a feeling that one of the previous owners installed a jb4 or similar and then returned it to stock before trade-in.

I would get verification of this because a bad battery was the first thing that came to mind.

[Fun w/N54]

Originally Posted by msjulesy

I would get verification of this because a bad battery was the first thing that came to mind.

This. And an unregistered battery would not charge properly and cause issues as well.

[Steve Theodore]

Battery is indeed the first thing to check/suspect.

[08tt335]

Update: i went to my car on saturday and the battery was completely dead. This morning i picked up a replacement battery and had a bmw tech meet me at my car to register it. After this, the car is still giving me the exact same problems. So I have no idea what's wrong. But the wipers go on and off on their own and every time I press the gas the radio cuts off completely. Any ideas? I just bought a warranty through endurance but it doesnt kick in until 30 days and 1000 miles.

[frenchi]

Use hidden menu and check voltage,seems like voltage regulator alternator problem ...

[TBN54]

Yeah, next thing on your list should be to check your alternator. Keep us updated.

[Abax335]

Alternator is an easy component to check, still sounds like a control unit bus issue. From all the lights coming off can be stemming from the jbe.

The recall was performed for the battery cable right ?

[08tt335]

Yes the bmw dealer comfirmed the battery wire has been replaced. I will have to check the alternator after work. How do I pull up the hidden menu?

[08tt335]

Also, my speedometer doesn't work. Therefore, the miles will not go up and my warranty won't kick in at all until this issue is resolved. Lol fml

[DirtKurt]

Did you buy it from a dealership? I would be going back to them, Looks like virgina has something called a used car window sicker and if it isn't filled out completely and correctly on both sides you may have the right to a warranty and or return of the vehicle.

[08tt335]

Yes, unfortunately i bought the car as is

[08tt335]

Update: i have opened the hidden menu to check the voltage on my car while it's running. In idle it stays around 14.0-14.1 but as soon as I rev my engine it started jumping up. By the time im at 2k rpm the voltage has reached over 17v and then the abs and other lights come on and the radio cuts off. But now the wipers arent screwing up anymore and when it idles again it returns to normal and voltage goes back to 14v. Im assuming this is definitey an alternator issue?

[dbond]

I'm with Abax335. The overvoltage due to faulty alternator/regulator sounds very plausible. A dealer worth its salt would have found tons of overvoltage errors in all modules starting from JBE on the first scan.

[08tt335]

[Dark_Knight_335]

Get rid of it. Drive it off a cliff, have someone torch it ...anything. It will be better than the alternative.

[Abax335]

Can you confirm an over voltage with a DVOM at the battery itself?

Now I'm heavily leaning towards that. We have been having alot of the n20 engines with bad alternators causing similar issues. Last one was a f25 x3 that was dropping off at certain rpms but was only throwing us VDM fault in one of the struts.

If you can confirm the same thing through a DVOM probably a pretty safe bet

[frenchi]

You can replace only voltage regulator a Bosch part and it's sold alone for about 100usd. Replace it and your car will be fixed !!