EPS light, SPORT Button Stays ON

[demos]

Hi fellas, my 2003 3.0 Z4 got the steering light on, no power steering, can't diagnose or communicate with the EPS ecu. I've read here that if the sport button also doesn't work then 100% it's an ECU problem. In my case the SPORT button stays on meaning the LED on the button is lighting, but pressing it doesn't turn it off it just stays ON.

A- So is this what is meant by "SPORT button doesn't work" which means it's an ECU problem? Or could it be something else?

When I delete ALL errors from entire car, all ecus, even though the EPS is dead, and turn ignition ON/OFF the EPS used to work and come back alive, and the power button works (I can turn it off/on by pressing it) and reading the ECU gives no errors.
Then after a few days, it would die and come back alive if I delete errors on GM5 (I'm getting Central Locking Relay errors on GM5).
Then few days when I let the heater on and idle car for a while EPS would come alive but light still on cluster so I cycle KL15 on/off and error would go away.

B- Would updating firmware on EPS solve this issue (tempt the car in any way to catch the moment where eps_e85 would come alive and update the software)?
Current AIF/ZUSB is 6763413 & never changed since 19.02.2003.

I'm trying to avoid breaking my back (bending over backwards to remove the motor), then breaking my wallet (shelling out 300 quid or so, with a possibility of getting unit back and being told oh it's no good get another one, or having it work for a day or so and re-sending only to be told it's no good, or I'm no good, or the torque sensor is no good...etc. as I've read on some threads here).

Thank you.

 

[enuff_zed]

Usually the light won’t come on, but if you cannot communicate with the eps ecu I’d still suggest that is your issue.
Where are you?
I’ve changed many of these now and can either send off a u/s one and get it repaired to fit to yours, or I have a good used one I could swap in for you.
Repaired is £295
Used is £100
To replace either would be £75 labour.

 

[demos]

I don't understand the options though, are you saying you could sell me a used motor for £100? If so, how far are you from Oxford OX4? Thanks!!!

 

[enuff_zed]

I don't understand the options though, are you saying you could sell me a used motor for £100? If so, how far are you from Oxford OX4? Thanks!!!

Ecu Testing will repair a motor and give it a lifetime warranty for £295.
If you cannot afford that I would sell you a working secondhand one for £100.
If you couldn’t swap it yourself I could do that for an additional £75, regardless of whether you fit repaired or secondhand.
However, I am near Norwich.
If you wanted me to come to you I would obviously ask you to cover my fuel costs.

 

[Mike6]

How old is the battery. Think I would look at that as a first step. If it's not that old try disconnecting battery for 15 minutes then try again.

 

[demos]

Ecu Testing will repair a motor and give it a lifetime warranty for £295.
If you cannot afford that I would sell you a working secondhand one for £100.
If you couldn’t swap it yourself I could do that for an additional £75, regardless of whether you fit repaired or secondhand.
However, I am near Norwich.
If you wanted me to come to you I would obviously ask you to cover my fuel costs.

Thanks alot, yes I'd rather much get a used one. I tried to message you but the system/forum wouldn't allow, can you post it to my address?

 

[enuff_zed]

Thanks alot, yes I'd rather much get a used one. I tried to message you but the system/forum wouldn't allow, can you post it to my address?

I’m not back from Grenada until 13th. Once you have 5 posts you can DM.
As long as you’re sure it’s not due to an old battery

 

[demos]

I’m not back from Grenada until 13th. Once you have 5 posts you can DM.
As long as you’re sure it’s not due to an old battery

Yes I'm quite sure I need your used EPS and at £100 I can't complain even if problem turned out to be something else.
I've replaced battery with a used but working AGM Silver Varta 80AH 800A, and I'm having a 60amp DC power supply connected to the car. The EPS has a mind of its own. I noticed in my case, the LED on the Sport it always ON when the ECU is dead. When EPS is alive, the LED on Sport button is OFF and the LED turns on when pressed & off when pressed again. When I turn ignition on and EPS is alive, it stays alive. I managed to update firmware, and it stayed alive all day. But leave the car overnight, come the next day, EPS dead, and only God knows when it'll be alive again.

Other gremlins in this Z4 the Satnav DVD keeps clicking, the driver's door lock cylinder isn't working it just spins with the key blad so I lock it via remote. Even with remote lock, driver's door locks the door but doesn't unlock, the thing doesn't pop up so I have to go from passenger's door. And the "P" parking LED always stays on. I leave the car unlocked cuz when I do lock it via remote the alarm keeps trigerring as it also has a mind of its own.

 

[enuff_zed]

I had the same issue with a door lock barrel. There is a small metal tag that pushes in to hold everything in place. I found it in the bottom of the door and managed to refit it to the barrel.
You may find that fixing that will make the door lock work again as possibly the barrel is holding the actuator in slightly the wrong position.

 

[demos]

How old is the battery. Think I would look at that as a first step. If it's not that old try disconnecting battery for 15 minutes then try again.

Battery was pretty old but I replaced it with a used Varta AGM 80ah 800amp battery that runs my F30 without any issues. EPS came alive for one day, well didn't drive car that day but had it on DC power supply and kept running querying EPS ecu all day, even turned ignition on/off couple of times it was find. Next day, EPS dead.

 

[enuff_zed]

Battery was pretty old but I replaced it with a used Varta AGM 80ah 800amp battery that runs my F30 without any issues. EPS came alive for one day, well didn't drive car that day but had it on DC power supply and kept running querying EPS ecu all day, even turned ignition on/off couple of times it was find. Next day, EPS dead.

And when the eps was dead, what battery voltage was there?
Is this perhaps a sign of a parasitic drain somewhere?

 

[Mike6]

I would still be thinking of battery before anything else even though you have swapped with another one. You will need a new one eventually and it's amazing how many wrongs a new one cures.

 

[demos]

And when the eps was dead, what battery voltage was there?
Is this perhaps a sign of a parasitic drain somewhere?

12.3V and I hooked up a DC regulated power supply setup to 13.5V and measured voltage to EPS motor the large connector with brown and red wires had 13.3V. Also measured resistance from Brown wire to chassis ground, zero ohm. There could be a drain yes, but I don't think that's killing my EPS, I just want to get it MOT'd so I can move around freely.

 

[demos]

I would still be thinking of battery before anything else even though you have swapped with another one. You will need a new one eventually and it's amazing how many wrongs a new one cures.

I agree I might get a battery after I get it MOT'd, gotta save some cash for other issues like driver's cylinder lock, passenger's window regulator, GM5 relays (can't even find Tyco/TE connectivity original ones any more, eBay's flooded with Chinese clones), SatNav screen, EPS. Oh and while it's been parked, the yaw/rotational rate sensor just died.