E85 Electric Power Steering Control Unit Resoldering?

yg54sg · Post by **yg54sg** » Fri Aug 11, 2023 4:00 pm

Brilliant, thanks for the tip re clutch pedal

r3vmatch · Post by **r3vmatch** » Sun Aug 13, 2023 10:34 pm

Hi,

Looking at image 20180303_213041.jpg , to my eyes it looks like there are breaks in the bond wires near the left / right corners, unless that is "by design" (which would be unsual to me). Perhaps this is causing the faults in the EPAS unit?

I am am Electrical Engineer by degree and experience and this type of mounting of a circuit in a housing was more common in the 1980s for use with 'hybrid' circuits, especially for high-frequency RF designs.

In this case it looks like a cost optimization to me, normally all of those ICs would be in plastic packaging and soldered to a rigid PCB that would have some connector attachment to the outside world (vs. bond wires).

yg54sg · Post by **yg54sg** » Sun Aug 13, 2023 10:39 pm

@r3vmatch the picture you mention is very similar to the glow plug control unit on a 120D 2004 , thin strands of wire from the PCB to terminals , these break and then the glow plugs stop working I will see if I can find a pic of the repair I did.

Rix · Post by **Rix** » Thu Apr 11, 2024 7:53 pm

So this seems to be an annual event around MOT time...

Took the car for an MOT, passed with flying colours, had a service done and brake fluid changed and they had to free up a piston anyway...

Car off ramp and the PAS light is on. No power assistance...

A quick bit of googling found this thread and indeed it seems like I'm another victim of module failure!

Took a quick peek under the column and not sure I like my chances of contorting myself into that position, seat out or not! Will take a more serious look at the weekend, spanners in hand! The NewTIS link seems to be dead so wondered if there are any other guides available re removal?! Wish me luck...

enuff_zed · Post by **enuff_zed** » Thu Apr 11, 2024 8:05 pm

If your code reader can’t speak to the eps ecu and the sport button doesn’t work then yes the ecu is goosed.
Take it off, send it to ECUTesting for £295 and get it back fixed within 4 days or so with a lifetime warranty.
A few simple tips which, if you are happy to pm me your mobile number I can WhatsApp you through the process.

yg54sg · Post by **yg54sg** » Thu Apr 11, 2024 8:12 pm

It could be the ribbon cable issue breaking like mine? I would drive it around for a couple of days maybe not city center, needs a strong arm but once your moving its fine, if it start working again on engine restart and your sport button works then its most def the ribbon cable issue. I have some videos of motor removal but unfortunately there is a lot of swearing and cursing of the German engineers while i'm upside down so prob not suitable for YouTube but DM me your WhatsApp and I'll send if you need them.

Rix · Post by **Rix** » Thu Apr 11, 2024 8:18 pm

You're both stars, thanks! Will PM you my mobile, ta. Indeed, no comms to module although I do get the anti tamper code on the DME which I'd not noticed before. My sport button has been disabled since my DME swap last year so that aspect is inconclusive.

The car presumably had got pretty warm whilst out on a test drive and sitting in the workshop so wouldn't be surprised if it works in the morning but clearly it's on its way out at very best.

enuff_zed · Post by **enuff_zed** » Thu Apr 11, 2024 8:44 pm

yg54sg wrote: ↑Thu Apr 11, 2024 8:12 pm It could be the ribbon cable issue breaking like mine? I would drive it around for a couple of days maybe not city center, needs a strong arm but once your moving its fine, if it start working again on engine restart and your sport button works then its most def the ribbon cable issue. I have some videos of motor removal but unfortunately there is a lot of swearing and cursing of the German engineers while i'm upside down so prob not suitable for YouTube but DM me your WhatsApp and I'll send if you need them.

Also, if its the ribbon cable that is in the torque sensor within the column, nothing to do with the motor.
It requires a column strip down and it's easier to swap in a replacement tbh.

Rix · Post by **Rix** » Sat Apr 13, 2024 12:26 pm

So I started the car yesterday morning and low and behold, no EPS light and functioning Steering! However today, went to try the same (mid day on a sunny day) and light back on and no steering...

This seems to suggest it's linked to ambient temp so hopefully consistent with the module being defective rather than the torque sensor/ribbon cable?

Yet to roll up my sleeves and tackle the extraction!

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