Relay – OKIEROVER.COM

I have a plan to light the exterior of the Range Rover Classic. I want to be able to turn on the exterior lights while I lay on my mattress inside. This is mostly to have a tactical advantage if something or someone is on the outside of my vehicle.

I want to be able to turn on a single light or with one switch turn on ALL THE LIGHTS. In order to do this I needed to come up with a circuit drawing for this task. I tried my hand but had little to no confidence that I had done it correctly.

So I consulted my best friend Mike to get a circuit drawn and to get a source for the parts. I drove up last weekend and had lunch with he and Paul and then went back to Mike’s shop. We sat and had a beer in his RV while we talked about lots of stuff and got caught up since we saw each other at my birthday part in October last year.

He scribbled a circuit for me. We talked about where to get the parts and he gave me the details. He buys parts that are for automotive use. He buys from them to build the trailer wiring conversions from military to civilian / civilian to military. He sells them on XM381.com if that is something you are looking for.

I took the graphic and re-drew it. Then from the parts I ordered after we met I cobbled together a loose circuit and tested it. Using the battery from the Range Rover Classic and some wires and two lights from my stock of lights I’ve salvaged from breaker’s yards.

I love it when a plan comes together.

Next thing I need to do is order some switches and 16 gauge wire and decide on the lights I want to install. I have some picked out, I’ll need to make a decision one way or another.

I took my time and puzzled this out and I’m so happy I got it to work. My drawing was “close” but would not have worked. Mike was so gracious to help me with this.

Thanks for reading, like and subscribe, and Happy Rovering.

If you’ve been following along I’ve been trying to find the parasitic draw for quite some time. I finally put my head on straight and dug in.

Having found the circuit that was giving me the trouble it was then time to call in the brains and ask some questions. So I called JagGuy. Mike is a genius and understands more about the physical universe than is possible for most mere mortals.

In our chat he said it about the time the thought was pulling up in the driveway of my mind, “You need to check your relay.” He said he’d look at the schematics (which he said were terrible by the way). It indeed came down to the relay. I have the WRONG relay installed.

I don’t remember when I came up with the fact the OEM relay failed. I do remember bringing it into my house were it sat on my end table and then in the drawer of my end table and then moved to the office? and then lost forever. SO I suspected the relay, I just forgot why.

So back to “the wrong relay” this is the one I had installed…..

What I should have installed was this relay…

You can see the slight difference. The 87a relay has 87a hot. the 87 87 relay is NOT hot all the time. How he came up with that I will never know. What he shared was the 87a relay might be the most common relay in the “relay world”. He has purchased and installed 1000’s of them making his trailer wiring converter boxes for military to civilian service [xm381.com]. He said they are common on fuel injections too if I remember the conversation.

Anyway, he said the far LESS common 87 87 relay is the one I needed. I promptly ordered one from Atlantic British an hour before he texted me back all the great details.

So there you have it. Something as simple as that can disable you. It is good to know that your can use an 87a in a pinch if your 87 87 fails. But you will want to pull it before you park it for any length of time.

UPDATE: The part has arrived and I’m going to test this weekend to confirm by parasitic draw is gone!

Thanks for reading and Happy Rovering.

Category: Relay

Planning the Exterior Lights for my Range Rover Classic Overland Rig (Post #707) 6/22/2025

Diagnosing Parasitic Draw on a Range Rover Classic: Part 3 (Post #680) 11/25/2024