I installed the DSE kit on an original RS that had been converted to a standard over the years. Still had the original RS wire harness and light switch. It was a simple and basic install, A four wire pigtail that jumps into the blue headlight wire, a parking light wire that installs in the open lead on the switch, a fused constant 12V jump to the fuse box ,and a ground wire. That connects to the control box with the four headlight leads coming out. When I pulled the switch, all lighting worked perfect, but not the doors. I first checked the ground wire for the control box, it sparked on me. So I checked all harness grounds and all were good. Testing showed 12V going into the box and nothing coming out. The two lamp wire leads only read about 11.24 at the last terminal conncter before the box. I did this without the headlight switch installed in the dash and no ground wire. Ran a ground wire to it and nothing changed. After several calls with DSE, They sent another box to me and I sent the original back to them, which they confirmed to be shot. I have checked over all the wiring four times, but still had the same problem with the second box. but now there is no voltage coming out of the switch for the headlight terminal. I moved everything to the bench and did a complete mock up including wiring to the new headlight motors, and I used a 69 switch (with good headlight lead) that I had. Nothing changed.
I really doubt that I got two bad boxes, which implies that they both fried immeditatley when I hit the power. It will be next week before DSE can try and determine what may have caused the problem with the first box, but I can use some help now.
The only fault I see in my wiring is not having the headlight switch grounded, but I wouldn't think that would cause that kind of damage. Am I wrong?
Here is something else I noticed last night, after reinstalling everything back in the car and doing one more check of the wiring. The ground wire on the control box is hot when the light switch is grounded only. I don't know if that is normal, a result from the damage, or the cause of the problem.
At one point I charged the battery and did get more than 11.5 volts at the connector, which is the minimum voltage requirement per DSE. I wouldn't think lack of voltage would short out the system either.
Is it normal to loose half a volt between a battery and the headlight connector? Assuming all connectections are tight?
Right now I'm going back and go over it all again and will probably be buying a third box on Monday. DSE is going to see what they can find out on thier end, but I can't install it without coming up with an answer.
I would appreciate any advice.
Thanks, Gary

Do you happen to have LED tail lights? The reason I am asking is, I do and you have to wire the motors into front parking lights. If not, the LED'S back feed into system and keep one or the other LED tail light board lit. This in turn burns up the module. DSE sent us a new module to replace burnt one and told us how to wire in. The way we have it now the headlight doors cycle 1 time when key is turned on. Then they stay closed until I operate head light switch. Hopefully new module will fix it to operare properly.