EPS Problems

[atenorio]

Hi Everyone!
Long time reader, first time poster.

I've been having some intermittent issues with my EPS as is common. From what I understand, if the EPS ECU goes, the sport button should also stop working and that's generally the criteria for a bad EPS unit that should be removed, sent to ecutesting for rebuild, etc, etc.

In my case, the EPS light will come on but I will still have a functional sport button. The steering will still be unassisted but the throttle response will change as it should. Has anyone had this experience and what was the diagnosis?

Much thanks!

Andrew

 

[enuff_zed]

Firstly of course you need to check the codes. This sounds more like a steering angle sensor playing up

 

[atenorio]

Thanks for the speedy response!

My code reader finally came in today. A few interesting findings...

1. I'm unable to communicate with the EPS system. However I did go in yesterday to look around and disconnected/reconnected it. I'll make sure tomorrow its properly connected and try rescanning.

2. The angle sensor showed a 'Slider Fault (adjustment operation)' error. I cleared that error and waited a few minutes to re-scan. No more fault code. Although I did notice when looking at the data stream that the steering angle would show something reasonable like 5 deg but with any input it would rail the sensor to 325 deg and wouldn't move off it.

So it does appear that the angle sensor is acting up but still unsure why the scanner didn't find the EPS. Does this sound consistent with a failed angle sensor but good EPS Motor?

Only the eps light is on and last I checked the sport button is still functional.

Thanks all!

 

[enuff_zed]

I think you need to sort the angle sensor first. It feeds the info via the DME to the EPS. When the EPS fails it is not unusual for it to stop communicating,
From experience if the sport button still works it is more likely to be the angle sensor.
Not done it myself but bigwinn has had success separating the sensor in situ and cleaning, adjusting the contacts.

 

[atenorio]

Hi again! After a few weeks and more diagnostic testing by my local shop they have concluded the EPS Motor to be the fault. I plan on removing the motor and getting it sent to ECUtesting...although I'll likely wait until the new year. A few questions before I get started.

1. enuff_zed I saw in some other posts that you have some instructions available through WhatsApp on how to remove/replace just the motor without taking the column out? I would love to have those and would donate of course

2. If I do decide to remove the entire column and replace the angle sensor + motor...does the angle sensor need to be re-programmed or is it plug and play? Is this worth doing or are the angle sensor less prone to going out than the motors?

Thanks again everyone!

 

[enuff_zed]

Hi again! After a few weeks and more diagnostic testing by my local shop they have concluded the EPS Motor to be the fault. I plan on removing the motor and getting it sent to ECUtesting...although I'll likely wait until the new year. A few questions before I get started.

1. enuff_zed I saw in some other posts that you have some instructions available through WhatsApp on how to remove/replace just the motor without taking the column out? I would love to have those and would donate of course

2. If I do decide to remove the entire column and replace the angle sensor + motor...does the angle sensor need to be re-programmed or is it plug and play? Is this worth doing or are the angle sensor less prone to going out than the motors?

Thanks again everyone!

If you pm me a number I can send the photos etc. but I’m away on holiday until January so may not be so quick to respond

 

[Arnie_one]

Hi, i think every peopele have issue with EPS (or they will have) , i send only motor to ECU.DE. Now i dont have any issue with EPS, 1 year and next 10Kkm whitout issue.

remove the EPS is not so dificult i did it 2 times i have twice same error - S0100.

 

[enuff_zed]

Hi, i think every peopele have issue with EPS (or they will have) , i send only motor to ECU.DE. Now i dont have any issue with EPS, 1 year and next 10Kkm whitout issue.

remove the EPS is not so dificult i did it 2 times i have twice same error - S0100.

Wow! You took a lot of stuff out!!
It can be done in about 45 minutes without moving the column at all. Including seat and steering wheel off for access

 

[Arnie_one]

enuff_zed:

Yes, then you are good 2 times i did it quickly.
- steering wheels out
- 8 screw for EPS (console)
- Licht module out
- many conectors

As you wrote 30-45 min and then everything back.

first i changed also low join assy, this was lot of work, also angle sensor.





lot of improvemnets i have did it...but i think this is fun for every BMW Z4 a fun