One of my clients has a Lexus sedan, probably around vintage 2000 that he’s really fond of. It is a good looking car, and has been pretty reliable for him. Lately he’s going through phases of needing to jump it every time he goes anywhere.

He’s taken it to a mechanic he likes a couple times to try to find the energy drain. I told him it could be tough to find those things. He had heard about some sort of kill switch on the battery so that he could isolate it from the short during his regular stretches of two or three days of not driving it. He’s an editor and does most of his work these days on Skype with clients around the world.

His man installed a device at the ground connection that does the trick, but he has to open the hood at the beginning and end of each trip. That was part of what he didn’t like about needing to jump it every time. I told him there might be some sort of relay that he could have placed under the dash so that he could do it remotely. His mechanic said he couldn’t find the hardware to do that.

I found this device on Amazon, not exactly a relay, it would require running the cables through the firewall to attach under the dash. I’m not sure how long those things can be, I know my BMW had the battery in the trunk, and it worked well enough with the long cables.

Most relays are temporary in nature it seems, they close the circuit for a second or two and then go back to default position of being off. Like a starter relay. On the other hand my BMW’s fuel pump operated with a relay that stayed on while the car was operating So what do you think? Could this device be placed under the dash and do the trick?

https://tinyurl.com/kkxcbwwc

__________________
Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K