Line 6 DL4 footswitch repair, did I just wreck my board?

[ShotgunTimmy]

Hello everybody!

This is my first post, sorry if it's in the wrong place - I have a problem with my DL4. The 1st footswitch stopped working, so I bought replacement switches and since they came in a bag of 5, I replaced all four of them. The 1st switch is now operating correctly, but now the 4th switch is not working, even though it was completely fine before.
I think I might have damaged the electrical component R32 on the circuit board when I was taking off the old switches. I tested it with a multimeter and there is no current flowing through it. I don't know anything about circuit boards, I was just following a youtube video... but would I be correct in saying that this R32 provides power to the 4th switch? I have tested similar components beside the other switches and they seem ok.

 

It is only my second time ever using a soldering iron, I didn't do the tidiest job, but I checked with a multimeter and my solders appear to be ok. However, as you can see in the pictures I had a bit of a problem trying to get the original switches off. I had no solder braid/vac so I had to use pliers:

Here is a pic of the back, switch 4 on the left, switch 1 on the right:

That last pic shows the first switch I tried to remove. As you can see, I made a bit of a balls of it, took too much off but it seems to work fine. I didn't bother adding anymore solder where it came off, because the video said that only the 2 parts on the left of each switch were needed. Could that gap I left be affecting that 4th switch down the line?

Appreciate any info from anybody who has knowledge in this kind of stuff, because I clearly don't!
I can take any extra pictures if necessary. It's difficult to get a proper clear shot of that R32 component with my phone, but even to the naked eye it seems a little bit scuffed. And the fact that the multimeter indicates that there is a problem there... well that has to be it? And  if that is the problem, what can I do now?

[WRGKMC]

This should be a lesson to you.  There is no such thing as preventative repairs in modern electronics.  If it ain't broke don't, mess with it. 

Chances are you overheated the switch and wiped it out.  Most modern switches are made of nylon or plastic. If you don't solder for a living you probably don't know how important it is to heat sink the connections on the cheap parts made today.  Most everything made today is robotically wave soldered with timing that is computer accurate.  They don't get overheated when affixing them to the boards. If you don't solder enough and try to match the speed so it doesn't overheat it only takes a second too long to fry that switch on the inside and melt plastic over the contacts. 

 

The Only thing you can do is to replace the switch again.  Be sure you clean up the solder points using a little nail polish remover and a Q tip too. The solder resin you leave behind has small articles of lead which can bridge traces if you don't clean up that stuff after soldering. This is very important on new circuits that use such low voltages.  it only takes the resistance of a fingertip to bridge a connection.  Leftover rosin is corrosive too so keep it clean. 

 

If you still have the used switches you can test them with a meter and see if one is still good. Otherwise, get a new one and change it out. 

In the future change only the part that fails. These aren't automobiles where you change an entire set of brakes at the same time or tube amps that have all the tubes or power caps at the same time.  They are designed to be disposable. When they break you buy a new one.  As A tech I've learned it is unwise to look for trouble.  Robotically built gear is much more precise then something hand built so change parts as the fail only.  Don't do something stupid like Cleaning all the pots in a piece or gear when one gets scratchy either. Clean only the one that's giving you the problem and leave the rest alone. Cleaning may temporarily rejuvenate a dirty pot by removing dirt trapped by lubricants inside the pot.  When you clean good pots it strips the lubricants and accelerates the wear on the carbon pads. you in fact accelerate their failure by trying to clean them. 

Pots, switches, connectors, any moving parts or parts that see movement are designed to work their maximum time without being cleaned so beware.  Electronics is not the same as it was in the past. Engineers have made the jobs of electronic techs obsolete by designing parts that will work without maintenance and should only be replaced when they fail.  (if you can even do that without screwing up the boards, components are so small now you need a microscopic soldering station for most components these days.  Multi layers boards make it dam near impossible to solder most properly too.  

 

 

[ShotgunTimmy]

Thanks mate I appreciate the reply. Yeah I hear you with the "if it ain't broke don't fix it", but I've been watching a bunch of youtube videos where people have changed all the switches on their DL4s, and I assumed it was a common problem so I figured I'd change them all. Of course, it would be the 4th and last switch that I would damage! But the 1st switch is the one I really wanted to change, and it's working now, so even though the 4th switch isn't working, I'm still happier than I was before the change!

" The Only thing you can do is to replace the switch again. " - I have actually already tried this, as the switches came in a pack of 5 so I had one spare.

From what I can see, the problem with switch 4 is that the R32 resistor is damaged, and that is what was providing power to the switch. I have a friend who is good with electronics that could replace it, but he said that he will need to know that value of that R32 resistor before he could replace it.

[bieke]

R32 resistor is an 8.06K 1% metal film resistor