Peugeot 307 massage seat switch failure

Could be a few things. Since you've got an error code, that's a good starting point. Have you checked the fuse box to see if the fuse for the seat is blown? Also, wiggle the connector under the seat while trying the switch. Sometimes it's just a loose connection. You can easily reach it by sliding the seat to the maximum position.

Yeah, I checked the fuses first thing, all good there. Wiggling the connector... good shout, I'll try that. But if it's not the connector itself, how likely is it to be the actual seat motor that's packed in? And is there any way to test that without completely dismantling the seat?

Motors do fail, but intermittent electrical issues are way more common, especially in older cars. Given the stored error and your mileage, a defective cable or plug connection seems the most probable. Diagnosing the motor without proper tools is a pain. Could save yourself some headache and have a workshop check the car. It's not going to break the bank.

Okay, appreciate the advice! Gave it a shot myself, but no luck. Bit the bullet and took it to the shop. Turns out it WAS a dodgy connection in the wiring loom. They re-pinned it and it’s working fine now. Cost me 95€, so not too bad all things considered. Thanks again!