z4 steering seized - EPS?

ex4x4 · Post by **ex4x4** » Mon Mar 28, 2016 10:06 am

Hi Folks -
My name is Alistair - a 44 year old maintenance tech for car manufacturing company. Ive owned and self maintained numerous cars over the years - more of a passion than a money saving exercise.
Im new to this forum, and unfortunately my first post is a request for some advice.
Ive trawled through lots of posts and web sites, but as of yet unable to find anyone with the same concern as my Z

I bought a 2003 2.2 Z4 late last year as a summer fun toy and part restoration project ( needed a bit TLC but nothing major)
I had drove for a few weeks without concern. Then I parked her up over the winter months, occasionally starting her and letting her get up to temperature - to keep the damp out.
Last time I started her the EPS light came on and stayed on. The steering is extremely heavy to the point that it felt like I would snap something if I tried any harder to turn the wheel.
Using certain posts and web advice, I ve tried without success to investigate concern.
fuse 22 - ok
fuse 64 - ??? unable to find.
Main power to motor - 13.6 v whilst engine running
main ground - good
Tried using a C110 diagnostic tool - tested eps - no faults found.
disconnected battery - still same.

Ive heard of a lot of concerns with intermittent ( sticky steering) in higher temps but this is constant solid steering in January temps in the UK.

what would be your advice - without breaking the bank for a new steering assembly???

Many thanks for any input
Alistair

mr wilks · Post by **mr wilks** » Mon Mar 28, 2016 10:22 am

First off welcome to the forum
Interesting topic as i recently purchased (knowingly) a Z with sticky steering or in worse case faultmode / light on dash & no steering assistance
I'm sure mine is battery drain / low power related but before i reached that conclusion my indy tweaked the steering column which removed any stickiness that was present before
Partway down the column where the motor & column connect there is a shim that adjusted one way makes steering mega stiff hence the other way makes it light .
Undo the torx or hex heads , mark where the shim is & literally 1mm either way has effect on smoothness .
Its another possible to try before swapping out the whole thing

Oh & don't forget the pics of your car

ex4x4 · Post by **ex4x4** » Mon Mar 28, 2016 10:44 am

Thanks for the reply - i'll certainly give it a go.
It just seems strange how the concern appeared. the car was fine then not - without been driven inbetween.
Once the rain stops - Ill get out and have a look at the shim. Ill post back any findings.
As for pics - I ll get some up on here when she looks a bit more presentable - she's parked in my garden at the moment - hibernating!!

mr wilks · Post by **mr wilks** » Mon Mar 28, 2016 11:00 am

ex4x4 wrote:Thanks for the reply - i'll certainly give it a go.
It just seems strange how the concern appeared. the car was fine then not - without been driven inbetween.
Once the rain stops - Ill get out and have a look at the shim. Ill post back any findings.
As for pics - I ll get some up on here when she looks a bit more presentable - she's parked in my garden at the moment - hibernating!!

Once you've found the part to adjust have the car running so as you can turn the wheel whilst adjusting the shim , should add i haven't done this myself , my indy did the work after i came across a mention of it trawling back through the forum

ex4x4 · Post by **ex4x4** » Mon Mar 28, 2016 11:26 am

Ive found one pic from when i bought her.
Quite a tidy car for 13 years old - just the odd battle scar here and there.

: z4.JPG (63.44 KiB) Viewed 3062 times

GuidoK · Post by **GuidoK** » Mon Mar 28, 2016 11:35 am

First check if it's a 'hardware failure' or a 'software failure':
Put the front on axle stands and see if the steering wheel turns lightly.
If it doesnt, there's some physical obstruction in the rack/column/knuckles etc. (rust/seize/broken gear whatever)
If it does, there's something wrong with the eps.

ex4x4 · Post by **ex4x4** » Mon Mar 28, 2016 11:41 am

Thanks for that. Fingers crossed something repairable for less than 2K!

ex4x4 · Post by **ex4x4** » Mon Mar 28, 2016 12:05 pm

well - just been out and raised car off front wheels.
steering is free as a bird with engine running -turning lock to lock numerous times without binding - it would appear EPS is functioning correctly??
When car lowered onto wheels - steering returns to being very stiff. - tyre pressures ok.
Have lubed the steering knuckle joints - still no joy.
May have to get it back up on ramps and remove under trays for closer inspection.
were getting somewhere at last

MACK · Post by **MACK** » Mon Mar 28, 2016 11:49 pm

ex4x4 wrote:well - just been out and raised car off front wheels.
steering is free as a bird with engine running -turning lock to lock numerous times without binding - it would appear EPS is functioning correctly??
When car lowered onto wheels - steering returns to being very stiff. - tyre pressures ok.
Have lubed the steering knuckle joints - still no joy.
May have to get it back up on ramps and remove under trays for closer inspection.
were getting somewhere at last

I think you have slightly misunderstood GuidoK regarding the EPS.
the fact that it turns when not loaded implies there is a issue with the EPS.
The fact that the EPS light is on means the car knows there is an issue and therefore there will be a code somewhere. Perhaps a scan on a better/different scanner is the next step as there is definitely something amiss and the car knows it. That or Mr Wilks' shim mod might be worth a go.

GuidoK · Post by **GuidoK** » Tue Mar 29, 2016 12:59 am

Actually I ment to steer the car with the front wheels off the ground but also with the engine off (so no power steering). To see if the mechanics work.
No strange notches, seizing or anything that could trip some kind of safety/issue in the EPS.
with the wheels off the ground there is/should be no resistance, so if there is, it's a hardware failure in the rack or so.
But apparently there isn't.

But indeed if you have a light, there is always a code.
If you cant find that code, the codereader is not compatible for that system (or the code reader is faulty)

ex4x4 · Post by **ex4x4** » Tue Mar 29, 2016 10:05 am

Ok cheers guys - I'll have another look today, and report back.

ex4x4 · Post by **ex4x4** » Tue Mar 29, 2016 8:21 pm

Ok so today I raised front end off ground and without ignition, turned steering wheel lock to lock several times - nothing. No grinding , graunching, squeeking etc etc.
So im now on the look out for a decent code reader ( unlike the C110 - which I suspect is counterfeit)
will keep this thread updated with my findings and photos where applicable.
wish me luck!!

Oakleyextreme · Post by **Oakleyextreme** » Tue Mar 29, 2016 8:45 pm

Hi and welcome.
I'm not as experience as some people on here when it comes to Z4 but I had a similar fault on my Honda S2000 with its EPS when it had a half flat battery, gave the battery boost charge and this reset the fault..
Just wondering if this could be the same as your car has not been used over winter.

GuidoK · Post by **GuidoK** » Tue Mar 29, 2016 8:56 pm

I think most people that are into real troubleshooting and coding get an INPA usb interface. (that's a (modified)KKL or Dcan interface which is advertized to work with INPA)
The software has a very steep learing curve (INPA/DIS/NCSexpert/ISTAD (rheingold)) and not all sellers have a good software install package but it's the software that can do the most, as it's the software the dealer use or even the factories use.
INPA: general diagnostic program for most bmw's up to the e85. Does advanced diagnostics and some coding (special coding tasks)
Runs under windows and needs EDIABAS as a sub program (ediabas=database interface for bmw; runs in background)
DIS: general diagnostic program. Runs under unix, so is used as an image with VMware
NCS expert: coding, for instance functionality for lights windows, roof etc
ISTAD: new version that replaces DIS and INPA. also sometimes donwloadable as 'Rheingold' (ISTA-D(iagnostic) and ISTA-P(rogramming) are the latest BMW tools that the dealer uses I think. They are usually used with an ICOM interface (very fast obd2 and fibre optic interface), but in the 'warez' community some whizkids made istaD compatible with the cheap kkl/D-can usb interface. All with the ediabas software running in the windows background)

Remember, all these programs are 'illegal' (warez), they are hacked and made to interface with a kkl usb/obd2 cable. So there is no real helpdesk or backup and the install can be really dodgy. There are sellers of these software that have programmed an installation program around it so it is a 'one click installation'. If that works ok or not depends on the seller.

They are definately not as easy to use as a C110 or something like an autel maxidas, but have more advanced possibilities. The most difficult thing is to learn how the software works and what you can do with it. If your not really into that it may not be for you.

firebobby · Post by **firebobby** » Tue Mar 29, 2016 10:24 pm

Oakleyextreme wrote:Hi and welcome.
I'm not as experience as some people on here when it comes to Z4 but I had a similar fault on my Honda S2000 with its EPS when it had a half flat battery, gave the battery boost charge and this reset the fault..
Just wondering if this could be the same as your car has not been used over winter.

These cars do suffer with low/bad battery issues, I would also check this too as it seems strange how the steering has done this while being layed up. Try and give the battery a good charge.

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