rear lock stopped working

[Denis]

I noticed at the end of winter my rear lock on my 100Q 1989 does not work anymore.

I push the botton and nothing happend, neither the little leds lights !! the rear module stay at unlock. I did exchange vac tube to see if it can goes to the lock position... works ok,, i putted back the vac hose. The vac unit on the rear diff works great,,, but the front module seems to not respond anymmore

Any suggestion ?

thanks

Ðenis