Mystery MC system outages

[doctortasman]

Hi all,

I have an MC Zetec 2.0tdci with 80k on it.

Had it in for a scheduled service a month ago - was experiencing rpm dips going uphill and although the problem was clearly the transmission oil needing a change they suggested a TCM update first (and tried to sneak the $90 into the invoice hoping I wouldn't notice).... I've since had the tranny serviced and all is much better there...

Anyway two days after the initial service I had the ABS, ESC (traction control whatever it's called) and the ERS (airbag) lights come on all at the same time - for about 10mins - and then all off together.... And then on again a week later (for a few days) and then off, and now on again consistently for 2 weeks now.... Always together, never reset on restarting the car.

I take it to be plugged into the hive mind and they tell me it's a LH front speed sensor fault code with an ERS comm code to go with it and that the two don't seem related. They tell me that they'll change the speed sensor, but it's not likely that would fix the airbag issue... As you can predict, changing the speed sensor did absolutely nothing....

Now after some datalogger action they are 'pretty certain' it's the tone ring on the front left - which requires a new bearing assy to fix.

I'm not convinced as it seems an unlikely failure inside a sealed bearing... And doesn't explain why the airbag light would come on... Just the ABS/traction.... Plus seems a little coincidental so close to the TCM software update.

FYI cruise control and hill launch are both inop as well.

I need ideas as I can't find anyone who's had all three go together and I don't want to pay them to investigate and likely find no answers!

My other issue is a slightly scary rattle from the left side, perhaps transmission when engine is under load <2k rpm... But one thing at a time!!!

Thanks anyone for reading - new to the forum so not sure if this is even the right place to post!

Cheers!

[Deo]

I agree it would have been better if they had left the software update for another time so that you could confirm that the oil service alone improved the trans.
But I doubt the TCM update has actually been a bad thing for you, I haven't heard complaints about it.

I would suggest a $20 OBD reader is a good investment for you and do a bit of DIY fact finding.

And perhaps look for a dealer that is more customer-oriented: pretty mean of them to charge for a software update to resolve substandard performance when you are already paying for a service too.

Sent from my GTi-9305 using bloody Tapatalk

[Deo]

PS - usual troubleshooting for widespread electronic gremlins:
* leave battery disconnected for 10mins (need radio code)
* replace battery
* check wiring for poor grounding
* any water in the car where it shouldn't be? Incl under the carpet

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