Volvo S80 2.0T 2000 ABS warning lights & speedometer

[vetjugote]

Hi,

I recently purchased a Volvo S80 2.0T from 2000. A while after, I suddenly started to get warning messages such as "Brake failure, stop when safely", "Left presence light faulty" (I checked and it works), "Alarm faulty..".
Also the ABS, emission control system light (?) came on, and sometimes the speedometer stops working.
I noticed this happens sometimes when driving over bumps, but not always.
This issue is intermittent and usually goes away but often comes back quickly.

I have read some online and seen that it can be the ABS module (broken solders), but before I find someone to repair or buy a new one, could it be something else?
Before I bought it, a locksmith was messing with the ignition switch while trying to make a new key (but failed), and it was after this all these issues started appearing.
I checked the fuses for ABS and they are good.

Any tips on what could be the issue would be highly appreciated.

Can a reset on the battery help (Pull out negative cable then positive and wait 30minutes or so before plugging back in with Ignition set to II)?
Is it worth buying a used abs module (less than 100euro) if that´s causing the issue?

Or if it's something with the ignition, is it easy to fix? I'm not super-handy but would like to avoid to go to volvo (expensive.)

(I have purchased a obd2 scanner which I will receive shortly to check for error codes).
Best regards

[RickHaleParker]

I have read some online and seen that it can be the ABS module (broken solders), but before I find someone to repair or buy a new one, could it be something else?

The odds it is the ABS module is 95% or better. I recommend you get a remanufactured ABS module with the defect permanently corrected.