Print
Category: Tech Tips
Hits: 1451

"Pins 1-5... this damned sure ain't bowling!"

 

f you want to add additional lights to your rig, you may want to consider using genuine Land Rover switches.

In terms of aesthetics and functionality, the genuine switches are hard to beat, and, at the end of the day, it's a cleaner-looking installation in my opinion.

But that said, there are a few things you should know.

 

 

Read More

 

Below is my account of installing several switches, relays, and all of the associated "whatnot" in Sherman...

Mounting additional lights to my rig wasn't without a few challenges. I already had three lights mounted to my front bumper...


Three Hella 4000 lights mounted to a Safari Guard bumper.
The two outside lights are "Cornering" lights, and the middle is a "Euro" light.

... and I had the relays triggering off of the positive wire from the old fog lights that originally came with the vehicle when new. This setup worked flawlessly for many years, but recently things started going south...

The switch to control the lights wasn't a clicker-type switch; it was a momentary switch that Land Rover installed when new. This switch controlled the original Land Rover lights, and the wiring was somehow connected to the vehicle's computer. Over time, the lights would simply not come on... or they would come on after 3-5 minutes... or sometimes they'd simply go off... with no reasonable explanation... other than some issue with the computer I can only guess...

When I decided to add additional lights to my roof rack, I thought it was also the prefect opportunity to change the switch controlling the lights on the bumper from a momentary switch to a clicker switch.

The cruise-control switch on a Discovery II is a clicker-type switch...


A cruise control switch from a Discovery II.
Pictured borrowed from Expedition Exchange.

Click once... it's on... click again... it's off.

An obvious problem is that the face of the cruise control switch has nothing to do with lights, but already having a "#2" light switch, I carefully removed the faces and swapped them. In other words, I took the face from the #2 light switch and replaced the face on the cruise control switch with it...


A "#2" switch from a Discovery II.
Pictured borrowed from Expedition Exchange.

Now that I had the switches, it was time to wire everything up. (Now I'm finally to the point of why I started writing this in the first place).

On the back of the cruise control switch, there are five pins numbered 1 - 5. In addition, there are 4 pins on the bottom of the relay. In the simplist diagram I could draw, the following is a schematic of how things connect together...


Wiring schematic foe a Land Rover cruise control switch and a fused Hella relay

I'd like to think the diagram is pretty self explanatory... though I could be wrong...

Obviously there's significantly more to wiring lights than what's displayed in the diagram above. For example, in my truck I have seven fused relays for the lighting:

  • Relay 1 controls the two Cornering lamps on the bumper
  • Relay 2 controls the Euro lamp on the bumper
  • Relay 3 controls the two Corning lamps on the roof rack
  • Relay 4 controls the two Euro lamps on the roof rack
  • Relay 5 controls the work lamp on the back of the roof rack
  • Relay 6 controls the left side of the "underwear" lighting
  • Relay 7 controls the right side of the underwear lighting

In addition, I have a power distribution box wired into the electrical system. Then I had to know which gauge wire was appropriate for what lights and relays and switches and the power distribution block and on and on... but all of that is outside the scope of this tip.

I wrote this tip to document the relationship between a Land Rover switch, relay and lights... and to show the professional-looking results that can be obtained by using the Land Rover switches...

I hope you find this tip useful.

As always, if you have any questions, feel free to ask!

-- Bill Mallin