Installed some KC lights today and wired the relay to my cruise control switch. Everything worked when tested.

Drove around tonight and got the 3 amigos plus flashing M/S, which in my experience has been a battery voltage drain. Sure enough, it’s DEAD. I am stranded.

While I sit here waiting, I am trying to think of what I messed up. When I get home I’ll post how I wired things. But for now, any ideas of how I could have wired it so that the battery drains without the lights actually being on? This thing has a relay and I wonder if I wired it wrong or perhaps not ensuring it is “pins down” (sitting on its side, in other words) messed me up. I’m at a loss for what to do.

edit:

CC SWITCH BLACK — KC BLACK GND
CC SWITCH YELLOW — KC GREEN LOAD
CC SWITCH RED — LR RED
CC SWITCH GREEN — KC WHITE BATT SUPPLY
There is one yellow and one white wire that both go to the battery positive connection, and one black wire that goes to chassis ground.

aha moment edit:
I have a Kenwood TK-7180 and 8180 installed. They run just fine. Today I tested a Motorola GM300 while the others were running. I wonder if those 3 killed my battery while I was driving? Nevermind the KC lights? That GM300 is a 40w unit.

Update:
Got a jump, car died as soon as jump disconnected. Battery has completely drained. Lyft home and leaving overnight. I’m flummoxed. I’m still not sure that the relay wiring isn’t to blame. Everything worked as it should (lights came on when switched, switch illuminated, etc) but I have no guarantee that it’s not draining somehow.

 

 

Which KC lights? I don't think it will draw power without being on. I've got the apollo fog lights and haven't had a problem.You can check the voltage at the light connectors with the relay switched off to see if its energized. I have a bunch of aftermarket lights and do-dads pulling around ~50 amps at full draw. I haven't had any problems with the battery draining while driving. Yours is pulling 20-25 amps, it should be fine. Can't remember how much the stock alt provides but it should be enough.

If your battery dies after the jump pack is removed, its likely your alternator and or battery. Either your battery lost a cell/plate and can only provide 10.5v, or your alt isn't/cant charge your battery. Check the battery voltage after a charge. Better yet, bring a battery when you go back to your car and switch it out. If it runs with the new battery, your old battery is likely dead. But if it dies shortly or while your driving, then your alt is likely bad.

 

You said something that reminded me...I had a LAUNCH tool connected when this happened and it showed 10.5 on the voltage reading. Maybe I have a bad battery and all this other stuff is ancillary. I have replaced the alternator (Oct 2024) but it was not a high-amp version.

 

Yeah you likely have a broken plate within the battery. Or discharged it enough that it no longer holds a proper charge. A new battery should fix it.

 

Got a new battery. Put it in, started right up. Within 10 minutes I was getting the M/S lights and 3 amigos. Pulled over and car died. Pulled ALL of my KC wiring. Interior lights brightened up but still need a jump.


Has to be the lights. Only variable that has changed and I’ve blown through TWO batteries now. Is my wiring wrong or do I have a short somewhere? This is insane.

 

It must be your alternator then. The new battery isn't getting charged by the alternator. Which KC lights are you running? Did you test to see if there was voltage at the light connectors? I've run KC lights pulling 20 amps for over an hour with no issues.
Check this forum for more information:
https://landroverforums.com/forum/di...s-88324/page2/

 

So it’s possible that the lights are a red herring even though they are the thing that changed in the setup before this happened? They are Apollo 60 lights. I wired them to my cruise control switch. I thought maybe I scraped a wire when pulling it through and accidentally shorted.

This tracks, though. Short battery charge gives me enough to start the car and move it to a safe place. Alternator on order…

 

Can you read to see if there's voltage at the pins when turned off? I have the same lights but the fog version and haven't had any problem with them. If it grounded it should've blown a fuse. Never hurts to double check the wires and if you wired everything correctly. Try using the switch it came with to rule out variables.

 

Definitely on my list to do. I have to go over to where I left it once I get my alternator and replace that, then drive it home. Once it's home, this is my list to do:

1. Disconnect negative cable and use multimeter to test for battery drain
2. Test KC relay
3. Test KC relay harness
4. Maybe install my Redarc dual-battery setup