Boomslang harness - buzzing relay

Here you go. This is the relay on my 1992 200TDi.


Pry the pink cover off the black base, using a small screwdriver in the small side slots.


Remove all the crap circuitry inside. I used a pair of side cutters to remove the remaining connections, then connect a wire across these two terminals. I used a piece of 2.5mm multistrand. Make sure you get the correct pins!!


Another view.




All the photos showing the wire, are taken with the base in the same orientation.

Why have you destroyed the relay and made a permanent connection?

Just realised the photos don’t really show the connections. It’s these 2 circled.


Also, I think the reason the relay was “buzzing” when the sidelights are on, is because with the engine running, there is a voltage sent through a “power resistor” located in the drivers wing. It supplies a lower voltage, to the lights. As far as I can tell, the boomslang harness plugs into the original light connections and uses them to trigger relays, to power its own connections that are connected to the lights. If that’s the case, then the lower voltage may be enough to trigger the relay contacts, but not high enough to hold them closed, so the voltage drops, opens the relay, the voltage increases, closes the relay, and so on.

kermit_rr said:

Why have you destroyed the relay and made a permanent connection?

Click to expand...

The relay is only for the dim/dip function. It wasn’t working and causing headlight issues, so I “bypassed” it. The wiring of the relay takes a feed in, and then passes it through a coil, and back out. All I have done is remove the circuit, and install a permanent connection.

Edit: if you search for the bypass relay, you will see that Land Rover have made a “relay” in exactly the same way as I have done.

For other bypass solutions have a look at these:
https://www.landroverexpedition.com/technical/bypass-dim-dip-relay/
https://www.landyzone.co.uk/land-rover/bypassing-a-dim-dip-unit.184641/
https://www.defender2.net/forum/post502300.html

Mick, chaps thank you for all your help. So went in behind binnacle and found the voltage transformer (that’s what tinternet called it) it was more like a large black heatsink. So unplugged it and all is fixed. No more buzzing and perfect working lights finally. It had all the wires going in as per the wiring diagram Red from the column light switch, Blue/red/white for main and dip beam and a few browns with a small white and brown which also feeds into the oil pressure switch. I can only thank you all and hope that this post will help others

All the best

Rich