I have been having issues with my braking system; the B.L.I.S. capabilities, traction control and ABS will disengage and display lights on the dashboard. Ever since the purchase of this 2011 VOLVO S40 T5 2.5L in 2018 I have had this problem. The brakes will usually scrape loudly where the whole neighborhood can hear, and stop when the B.L.I.S. capabilities, traction control and ABS appear on my dashboard indicating they're not working. This usually occurs after starting in cold or cool weather, however, in the summer the problem hardly ever arises except when i turn sharply or when im randomly traveling down the highway. Any ideas? I've had a diagnostic 6 months ago and they said the brakes looked fine . I am going to inquire further on this date for more information.

 

Some light reading.

https://www.volvocars.com/en-th/supp...nance-for-blis

so you are saying your car makes a loud scraping noise when braking and your shop says the brakes look fine???

BLIS aside, your traction control and ABS are part of the same system and rely on the speed sensors on each wheel, the transmission speed sensor etc. The ABS computer talks to the TCU and ECU so any time you have a display light on the dashboard, I'd expect to have a stored fault code. Best to have a dealer with VIDA DICE scan the car to see if you have and fault codes which can indicate if you have a wonky speed sensor, any communications errors between the computers and then have them do a reset of the BLIS. Any loud scraping noise is something physical - so a proper wheel's off inspection is also in order. Could be anything from a bent brake backing plate to somebody installed incorrect pads etc.

 

Yes, the shop did a diagnostic and the sensor brought back some abs module codes I.E. faulty sensor, but is that what would cause the scraping? They said my brakes looked fine. Let me paint the full picture as well to what would happen with the car. In the winter season when i would start the vehicle and drive off as soon as i would brake the wheels would scrape or grind for every time the tire rotates during a brake. This would persist for a little bit and either the noise would disappear as the car would drive and heat up, or it would turn off the abs and blis functions and the sound would stop.this only happens in the cold weather.

 

The Volvo rotors can rust VERY quickly, particularly in the winter when they're subject to slushy salt-laden moisture. Mine would rust in Arizona (of all places!) after a wash. Yep, a little scraping / noise for the first couple easy applications of the brakes, and then silence. I can't say it was ever anything that would alert the neighbors though - just a low-level grinding / scraping you could feel in the car.

 

agree its pretty normal here in the northeast for brakes to be noisy rolling out of the garage when its been raining or the car's been sitting. Mine usually get quiet after 1/4 mile or less.