On several occasions my 2015.5 S60 has had what the dealer calls "cascading software problems." This week the ABS light came on, a few miles later the air pressure light warning came on, then the ESC light, then a brake warning and finally a faulty transmission warning. The next morning, no problems. The next day it started again but eventually the lights went out. I've got to where I assume none of these problems are real. Just "'cascading software problems." It is not always these lights. Once it began with the windshield wipers starting and refusing to stop and then cascaded. Another time it was the gas lid opener on the dash that preceeded the cascade. Does anyone else have problems like this? The first fixes were on warranty but now I am having to pay. What can I do?

 

Does your car need a new battery? Typically they are replaced every 5 or so years

 

Never heard of "cascading software problems." I think that's BS - your "software" is not going to do that ---

But I've certainly seen problems like that many times, and it happened on the wife's 2020 xc60 recently and was fixed under warranty.

What is always the problem? Water leakage into the passenger compartment and that water getting on/into a control unit or connection. The water is usually not visible until you remove the carpets.

Remove carpets, dry them out, fix the leak (maybe leaky windshield or a sunroof drain is a common problem), and replace or repair the damaged module or corroded connection.

A Volvo Dealer (or anyone with a VIDA subscription or the stolen/hacked VIDA 2014d for a 2015) is able to scan the car and if all that stuff is going on - there will be multiple codes and VIDA even has a timeline showing you when they were all set.

A compatible scan tool can give you that information also.

 

The dealer replaced 3, 2 under warranty.

 

point about checking the battery and electrical connections is that the sensors typically report back a voltage where the computer compares to an expected threshold. Low system voltage can mean you trigger a false positive. Bad connects or wiring same deal. If the sensor were bad, the fault code would simply return. Unfortunately, there's no easy way to find a root cause here - VIDA is the best tool to get some clues but from there the tech will need to start doing some additional inspections, testing etc, which may involve opening the dash to access modules that appear to be in a common service path for the various sensors/devices which reported a fault. I agree with Hoonk's comment on cascading software problems. I think that's the dealer's way of saying there's a common fault that is causing a series of seemingly unrelated false positive fault codes.

 

I took the car to an independent garage that specializes in Volvo. Mechanic said it was a faulty wheel sensor which set off the air pressure, abs, transmission, speed control and other sensors. I surely hope he's right.

 

A bad or damaged abs sensor could certainly cause a variety of problems - let us know how it works out.