whelen roof top lightbar

Has anyone had an issue with Whelen lightbar with 4 strobes and half working and the other half not? I tested all lights were operational and internal fuses were good. Is there a reason half would work?

I happened to fix a previous installers mistake. He tied into the rear wiper 12v+ wire and ground in the molex plug at the back of the switch. That was powering both the relay and switch to lights. Happened that the van went in for work at a dealership and then the driver used the lights and smoke came from behind the dash. I guess the tape he wrapped around wires didn't hold and caused a short. I re attached wire that was cut and soldered it and then taped. It had 24 awg speaker wire run across dash and around steering column. I had to remove this and run the wires to lights through firewall.
I ran the positive and grounded the wire under hood at factory screw. Hooked up the switch and relay to an acc. off ignition. grounded these at factory ground in kick panel. It worked like a charm, seems a tad brighter then before.
Would a lower amperage of 12v+ cause these lights to have an issue? I think it might have been part of the reason the lights were not working right. My boss had me run wires from the side that worked to the side that didn't and I didn't think it was a great idea but the lights worked. Let me know what you think of why the lights on one side quit working.