I’ve had four or five people friends ask me to repair their Line 6 DL4 delay / loop pedal now. The problem is always quite simple – the pedal simply won’t turn on at all! The repair is just as simple. (I dread to think how many of these might have been thrown away when they could have been so easily saved.)
Basically you just need to open the pedal up and reseat the EPROM chip (carefully prise it out, then put it back in again). It takes three minutes and requires no soldering, as shown in this handy video I’ve made for you. This was 100% successful with all the ‘bricked’ DL4s I’ve received, but obviously I take no responsibility if you damage yours further!