VDC lamp on solid, brake sys lamp flashing, NO check engine - ideas?

[kattz]

Before I run this to the local dealer, looking for ideas here.

2012 Legacy GT with coilovers, has new tires, complete Brembo conversion.

Intermittently, regardless of road condition, the VDC caution and the brake system caution will illuminate.  The brake warning lamp is flashing, the VDC lamp is solid.  No check engine or other fault indications.  No codes set.

During this time, the vehicle drives fine and there are no brake issues that I can find.  Everything working normally.

Did observe hill holder not working during this time.

After cycling the ignition, the lamps are out.  They might come on after 2km, they might come on after 200km.

I didn't put 2+2 together until just now, but when the previous owner and I were driving it around, during several trips there were no issues.

After I completed my transaction with the previous owner, I had to take it back to the tire shop for a rebalance of tires.  After this, as I was driving about 10 minutes, this was the first occurrence.

Ideas, please?

Edited August 6, 2023 by kattz
Extra info

[kattz]

Issue may be found. Kind Subaru dealer pointed out using their scan tool that I had a brake pedal switch adjustment code that was hidden.

However, no issue with the brake pedal switch. There is a relay underneath the dash that you can hear turn on the brake lights when you press the pedal. What's giving me the code is that the relay is taking five seconds to open back up after releasing my foot from the brake.

After so many occurrences of this,  especially going around a corner and the brake lights are on and you don't have your foot on the brake pedal, the vehicle says "screw it, I quit" and gives you a fault.

Dealer says it's the LED tail light bulbs. He said try a newer type or just take some of them out and see what happens. I think taking some of them out will make the problem worse and so I'm looking for a German pinkish red color LED like I had in my Audis that has the same resistance as an incandescent bulb.

I'll follow up when I get to the bottom of it, but so far, not a real break issue as much as a electrical issue. Figured I'd post it up here so others that may have the problem can see it. Cheers!

Edited August 11, 2023 by kattz

[m sprank]

Maybe you can find the proper relay that can handle the lower amp draw of the LED's as well.  IDK. 

Like replacing the turn signal relays to stop the hyper flash when swapping to LED. 

[kattz]

I kinda stopped going down this path because the lights going off longer only happens AFTER the VDC and brake warning lights come on.  If not on, you hear no relay action at all under the dash and the brake light response is instantaneous. 

I didn't consider changing the relay.  Thanks for that tidbit.

Edited August 21, 2023 by kattz

[m sprank]

Its always something with modded cars.  I had to replace plenty of turn signal relays in LGT's for the LED conversions.  Good luck!