Blind Spot Monitoring Sensor Module

[joey87]

Hey all, I have a 2018 MK7.5 Golf RLine

The blind spot monitoring has stopped working. I have tried turning it back on through the settings however it says, "function not available". From some research I think it could be the BSM sensor module...would this be right??

Any ideas how much it would cost to repair this? Either through a dealership or DIY (the car is now outside of warranty).

[DV52]

@joey87: hmm...... given the scarcity of information provided, it's difficult to be precise as to cause. The primary part of BSM is the 2 x radars located in each rear quarter panel - but BSM is still reliant on other functions on the CAN bus.

Do the BSM warning lights on the wing mirrors illuminate briefly on ignition switch-on (it's a self test)?

My suggestion is to find a forum member that lives close and has a diagnostic cable - then get a scan report taken ofrom the car to identify the real problem. It can remove much of the guess work

Don

[joey87]

Thanks for the quick response Don.

No...the mirrors don't illuminate when I switch the Golf on
I did the same for my wife's Mazda and it did illuminate on ignition.

Hopefully VW are still open during lockdown haha

[joey87]

@DV52 Do you know if it's difficult to install a BSM module?
I could take the rear panel off but is it easy as 'plug and play' with the new module? Do you think you would have to go through the calibration process?

[DV52]

@joey87: I've not actually replaced one of these radars, but according to the repair manual for a MY15 golf - the actual physical install doesn't look difficult.

Personally, I never start replacing modules in a car unless I first do the necessary diagnostic work and the results point to a faulty module.

As I understand your case, there isn't a clear indication of a faulty module. Plus you have the problem of deciding which BSM module to replace - the left, or the right side module?

And, after the new module is fitted - you will need a diagnostic tool to align the long-code string and the adaptation channel values to the settings in the old module

Finally, according to the VW manual, the calibration process for the OEM module requires a special target with integrated laser pointer and a bunch of other bits-and-pieces (including an ODIS based guidance function).

I'm not sure if after-market, non-OEM radars are self calibrating

Don

[joey87]

@DV52 - thanks Don.

Looks a little more complex than I initially thought. You're exactly right...do a diagnostic first. I have an OBDEleven Pro arriving soon, so hopefully that might give me an answer (plus a few cool mods).

Failing that, I did call the dealership yesterday and they said they could do I diagnostic to fault find (for $220 - a bit steep I thought but nothing new from VW haha).

[joey87]

Update --- I ended up taking the car to the dealership today and paid the $220 for a diagnostic (car is out warranty). All it was in the end was a software update which they were able to complete fairly quickly. No new hardware was required and blind spot monitoring is now working.

I did plug in my OBDeleven yesterday and it picked up the faults however, I wasn't willing and experienced to try and reset, code, play around etc.

FYI - I did call another VW dealership to enquire about sensor modules and installation (worst case scenario). Quote was approx $700 for each module ($1400 for master and slave), plus 4-5 of labour.

[DV52]

I did plug in my OBDeleven yesterday and it picked up the faults however, I wasn't willing and experienced to try and reset, code, play around etc.

hmm...... if this was my car and I had just paid $220 for a software update that was meant to solve a problem that randomly appeared and if the module still had errors after the fix- I would make my problem the dealer's problem!!

If all you are doing is reading the module errors with OBD11 (i.e. no changes made to coding values)- there should be no issue giving the dealer a copy of your scan results.

Don