I'm trying to hardwire my radar detector to the driver side kick panel fuse box, and I got the add-a-circuit fuse piggyback thing from Advance Auto Parts, and for some reason, it's not working. I put it in the heated mirror slot and tried it also in the cig lighter slot. Neither way would power the detector on and the device it was piggy-backed to wouldn't work either. Anyone have any ideas? It's driving me crazy that something that should be so simple is becoming a pain in the ***. Thanks.

 

Some detectors don't work off of 12v's They would have a small step down transformer in the original cigarette lighter plug. I would start with making sure your device operates on 12v's. Than using a volt meter or circuit tester ensure that you have 12v's at the wire that plugs into the device. Good luck.

 

Well I'm using the hardwire kit that came with my Whistler Pro 78 and it has a 2 amp fuse on the wire already, so now it has the 10 amp fuse from the add a circuit and the 2 amp fuse on the positive wire. It will still work like this, correct? My main confusion is the fact that I put a fuse in each of the 2 slots on the add a circuit, put it into the cig lighter fuse slot, and then connected my radar to the cig lighter with that power cord and it still wouldn't work. So it almost seems like the actual device isn't working. I'm almost out of ideas.