Both seats stopped heating at the same time. The lights on the switches don’t light up anymore either. Winter is coming to Colorado- where do I start to try to figure out the problem?
If you have the owner’s manual look for the fuse box legend to see which fuse protects the seat heater circuit. Check it first. No manual? Look up on line or just look at the box, it may have some circuits listed next to each fuse.
If fuse is good, locate and test relay(s) associated with seat heaters, if used in circuit. These may also be part of fuse box/load center.
I also have a 2001 Forester, and within the last two years various switches and light bulbs have started failing. If replacing the fuse doesn’t fix the problem, try replacing the switch itself. You will have to buy replacement switches from a Subaru dealer. Instructions for getting at the seat heater switches can be found online or in a Haynes manual.