Q: I own a 2020 Subaru Forester. The maintenance guide suggests a brake fluid flush every 30,000 miles/24 months. I have never owned any vehicle that has recommended this with such frequency. The brake fluid in the reservoir is very much a honey gold color but I presume this may not be indicative of the fluid circulating. Is this really necessary or is this one of the rare manufacturer maintenance recommendations that is not justified from a mechanical point of view?
G.K., Allentown, Pennsylvania
A: Brake hydraulic system designs may vary by manufacturer and may factor into maintenance schedules. You may be able to extend your fluid flushes by testing the brake fluid for signs of corrosion that can lead to ABS problems. A test strip product such as Strip Dip may show issues or possibly prove you may not need a fluid change.
Q: The 2015 Subaru Forester is designed so that the headlights remain on even when the ignition key is in the off position. Is this a standard design feature for most cars? It can cause battery issues if driving with the headlights on during the day in rainy weather and then stopping at a rest stop for a break while remaining in the car. If you don’t either turn the headlights off or physically remove the key from the ignition, you could end up needing to jump the battery (no fun if you are on a trip).
W.S., Portland, Connecticut
A: Consider it a feature, not a bug. When you select the automatic headlights on/off feature, the lights stay on long enough for you to safely walk away from the car. If you leave the key in the ignition, the headlights are a reminder that you forgot to remove the key. It is a bad habit to leave the key in an unattended car.
Q: Our 2014 Kia Soul has a little over 40,000 miles on the clock. I’m thinking it is getting close to time for replacing the serpentine belt, (which looks shiny and new) since I believe the Vegas temps may hasten its demise. I would much appreciate your thoughts if indeed it would be time to replace the serpentine belt.
B.P., Las Vegas
A: The serpentine belt, the one that snakes around the accessory pullies on the front of the engine, doesn’t usually snap suddenly. Small cracks in the grooved side are normal, but chunks are not. It is unlikely your belt is worn, and you can check it with a plastic tool that many parts stores give away.
Q: I leave my key fob in my unlocked car; the car is in my garage, which is locked. Does leaving the key fob overnight in my car drain the key fob‘s battery?
B.L., Schaumburg, Illinois
A: The key fob battery won’t drain prematurely but leaving the fob inside some cars may keep some control modules awake. That might put a drain on the automobile’s 12-volt battery.
Q: You recently responded to a reader who was looking for a locking gas cap for his 2001 BMW Z3 roadster. I have a 1998 BMW Z3 roadster and recently discovered that my gas cap was missing. I never locked it. My BMW dealer told me they don’t make the part; there is no substitute. I ended up purchasing a nonlocking gas cap from a supplier my son-in-law found that supposedly will pass emissions testing. We’ll soon see.
M.C., Columbia, Connecticut
A: If the check engine light stays off, the new cap is doing its job of sealing properly.
