405's have two aux. belt tensioners. One at the bottom (manual adjustment with 6mm Allen key), and a spring loaded one at the top. On my 405 '96 1.9td, the spring loaded one seized, so instead of paying out around 80 GBP for a new one, i got a slightly smaller belt. works a treat.
Drive less! Or don't drive at all ;-]
peugeot coupe
The drive belt on a Peugeot 206 should be change in 80,000 miles. Failure to change drive belts at the appropriate time can result in expensive engine failure.
Peugeot
RAM
Peugeot 207 S2000
One way is to use the auxiliary contacts on the motor contactor to close a separate source supply to drive an auxiliary relay.
The speed sensor on a Peugeot Boxer is on top of the gearbox. It is near the driver's side drive shaft inner CV.
It was a Peugeot 403 2-door convertible
If I understand your question correctly, you are asking about a pulley / drive belt tensioner. The drive belt turns the alternator and other auxiliary equipment (sometimes power steering pump) from the crankshaft pulley. The belt tensioner is fitted adjacent to the belt and keeps it under tension automatically by use of a spring. Looking under the bonnet from the front of the car the drive belt and alternator are to the left hand side of the engine.
It was a Peugeot 403 2-door convertible
(Australia) in the right hand drive Peugeot 308 the bonnet release is on passenger door frame, in foot well. A long skinny leaver.