Non stop wipers - need help

[MajorBob]

This is odd, and i cant find anything helpfull online, I have a 2012 138i e88 vert. tunr the car on and for about 5 minutes the wipers work normally as the should, all funtions work. About 5 min in, the stay on and will not stop regardless of control from the stawk. Only way to stop them is to turn the car off. I have removed the arms becouse o dont want the windshield sratched.

What i have tried: two different JBEs, two different Relays, replaced the Wiper stawk, Replaced the rain sensor, opend up the wiper controler and cleaned the contacts. Also, there are no wiper codes in ISTA.

Im currious on what suggesting this group may have to try next or if anyone else has experinced this?

Thanks!

[Lester]

Do you still have the original battery in the car?

[desertman123]

Originally Posted by Lester

Do you still have the original battery in the car?

And the voltage regulator off the alternator is giving a healthy output? Should be around 14v.

I mean, if the power delivery for the entire car were wonky, you'd USUALLY see the dashboard light up like a Christmas tree, and other issues pop up besides just the wipers.

The JBEs were coded with the settings and VIN that matches the car, right?

Might be time to start hunting down a corroded or loose connection. You've already done most of the things people would suggest.

It's probably worth posting this on the E90 forums as well, as it's not 1 series specific (all the electronics are the same at least)

[MajorBob]

thanks for the replies, yep, JBE is coded for the car. Battery is a new H8 AGM. Ill check alternator output but nothig popped up on ISTA. I may try swaping out the entire sterring wheel controls next. I swaped the stalk, but the control board within the module is still the original and thats about the only replacment part i can think to try next. and yes, Ill post this on the e90 forums. Im sure they get a lot more traffic. Thank again!

[Lester]

If the motor is getting power with the wiper switch off, then the culprit must be the relay, or a short somewhere in the power circuit. One needs to start tracing voltages back from the wiper motor. But easier said than done.

Tough one.

[Lester]

Is it coincidental, that a number of users on this forum are experiencing various electrical problems with their 8-12 year old models? Then when asked, they reveal that they replaced their battery 'recently' and that it was 'registered' by a process that may have been completed properly (or not).

Here is what the experts say:
https://www.bimmer-tech.net/blog/ite...d-registration

Before we dig into the process of battery registration, let’s focus on what BMW battery registration actually is. To put it simply, battery registration is a process of updating your vehicle with information that a brand new battery has been installed in your car. What's important, it should be performed each time you change the battery in your 2002 or newer BMW.

As your battery gets on in years and gradually loses its charging capacity, the vehicle adjusts the amount of energy needed to recharge to operate at optimal levels. The older the battery the more charging it requires. Registering your battery lets your engine control module (known as DME — Digital Motor Electronics) know that a new one is installed and as a result, the vehicle will reset the old battery statistics and won’t try to overcharge the new battery thinking the previous one is still inserted.

Apart from the registration procedure, you also have to code your BMW computer. It’ll be necessary each time you replace your battery, no matter its specifications - whether your battery is similar or extremely different from your old one.

Why is battery registration important on BMW?
The electrical system of BMW models manufactured after 2002 got very sophisticated, as it started to adjust charging to the age as well as the type of the battery. If you’re changing your BMW battery for a new one having different capacity or type, your DME has to be updated with this info. It happens for example when you’re switching between batteries with lower and higher cranking ampere ratings or swapping a Liquid Lead Acid battery for an AGM battery. However, swapping your old battery for an identical one also doesn’t free you from the obligation to go through a BMW battery reset procedure, as your vehicle has to program the battery capacity again.

What happens if you don't register BMW battery?
Registration is required so that your car knows about the changed specifications and can adjust to the new battery settings. Otherwise, if you don’t properly code BMW battery, it could result in many electrical problems; the battery life may decrease, you could overcharge or undercharge your battery, or in the worst case scenario, cause considerable damage to your vehicle’s alternator and electrical system — at this point your battery may fail prematurely.

What are the electrical errors that might occur? Certain modules of your BMW may turn off as a consequence of your car presuming that the battery life is low and wanting to save it. So, at that point your windows and mirrors may not close/open, your radio and interior lights might not work properly, or other modules not needed for starting or driving a car can fail.

Which BMW models require battery registration?
All BMW models manufactured after 2002 require battery registration, as they are significantly more advanced in terms of electrical environment, which aims to improve the gas mileage. Models developed since 2002 are equipped with the system of Intelligent Battery Sensors (IBS) that contains micro processors monitoring and measuring charge, discharge, voltage, current and battery temperature.

[ptpending]

the wipers will be non-stop when PTCAN transmission is disturbed

[MajorBob]

Thanks again everyone! It turned out be the lateral acceleration sensor (Little black box under the carpet in front the drivers seat). I found one at a local pick and pull and low and behold the problems are solved. The wipers works as they should and no more ABS codes. All is well! Crazy, would never have suspected this as the couse but got some some great tips on e90 site.

[MajorBob]

FYI, In case anyone is interested on the DSC codes this also fixed:
D370
D371
D372