my vehicle is a 99 disco 1 ,,
I have wired a brake controller at the brake light switch above the pedal, and just above the vacuum switch for the cruise control. This seems to work - Intermittently!! Causing me to have to manually control the trailer breaks (not good)

researching, i found this.. (admitting - not the same vehicle but made me worry)
"On most vehicles this can simply be connected to the mechanical switch behind the brake pedal that activates the brake lights. However the Range Rover LM, like its relative the BMW X5, uses a solid state Hall-effect sensor for this function, and connecting anything to it is not recommended. (The BMW X5 site has some interesting discussion on this topic). The sensor's status is detected by the Light Check Module (LCM) which controls all the vehicle's lights, so the best thing to connect to is the LCM output that tells the trailer ECU that the brake lights are on. (Do not select one of the other outputs that controls the actual brake lights, because these can carry bulb test signals even when the brakes are not on)."

Thus my question for you D1 experts .. does my D1 have a hall effect sensor that could be causing the issues or was my (possible) sloppy wiring the best suspect?

This is a vehicle I love and want dearly as a tow vehicle for my 17ft TT that will get me to some great off road locations...

Thanks for your help!

r

 

I connected mine to the wire that runs to the brake lights, never any issues with it.
It's been a long time and I can't remember exactly where I tapped the wire, I'll have a look later today.

 

Done quite a few of these.
Several on D1's & D2 for the horse crowd including my own hauling Paso Fino's.

I never interfere with the basic vehicle wiring harness other than take a tap signal.
So basically run a #12 or #14 from the fuse box protected by a separate add on 30A fuse to your trailer connection for brake actuator feed. Some have preferred under the carpet others by loom protection under the body to the "7 pin connector.

For signal actuation tap off the brake switch with a # 16 wire to a new add on relay for relay signalling then run a #14 from the fuse box source to the new add on relay for power actuation of the trailer brake module and of course ground (earth) the
remainder relay connections for good relay operation.
This is the way to do it on later vehicles with more Can Bus complication like Sprinter vans et al. Failure to do this can seriously mess with vehicle communication on some vehicles.
Remember don't let the smoke out!
All electrical wiring has smoke built into it; the fatter the wire the more smoke comes out when queued to do so by carelessness. When 24volts is present it can get spectacular. In short a "phore" moment!
T/V

 

Thanks all.. Tuercas, do you mean the smoke i saw right after that little metal pimple on the frame showed up? I hate having to grind off those bumps. They usually have some weird wire stuck to them too..

I am thinking a wiring issue but just wanted to confirm these did not have that sensor type relays that monitor the amps (or something) to determine that a bulb is out.

my reason for this thinking is that the controller was working fine till i removed some tail lights for some rear bumper mods.

Note that my activation line to the controller is off the brake pedal switch which has 3 wires .. and I was worried that i may have pulled the power from the wrong one even though I used a tester and the one I chose only activated when pedal depressed.

I never confirmed the purpose of the third wire and if the "wrong" one had a load or amp value that was confusing the controller now that some lights are missing.

oh yea... Tom -- other than the license did you get the antichrist name idea from that Australian movie? if so,, what was that movie name? With the coke bottle falling from the sky? Was thinking of that awhile ago and i cannot remember..

Thanks all

 

Question
Whose controller are you using?
T/V

 

Circuit protection should be a self-resetting circuit breaker, not a fuse.

If you have a fuse and it blows, you'll permanently loose trailer brakes until you replace it, which is hard to do while driving. The results could be disastrous if the fuse blows.
With a self-resetting circuit breaker at least you'll have trailer brakes intermittently until you sort the problem, which you should do as soon as you can safely pull over.

 

I have a hopkins InSight (proportional) that have the three units separated. The display on the steering wheel housing, brain on the left flooring wall just below the hood release and the override-manual brake slide is on the dash kind of where you would reach for a trailer brake handle on a semi.

I also have a 20 and 30 amp breaker set in the engine compartment for the controller power source and the trailer battery source. All have been ran with fresh 14 and 16 gauge duplex (sheathed) wire as needed and a fresh ground at the hitch, (no rust)

I really like the controller set up.. you can see it without having to hunt for it.

Does anyone know what that third wire is on the brake light switch?

thanks again all

 

Scary. Maybe you need to re-do the wiring and try a new brake controller - they have some nice ones at ReeseHitches.com and they usually provide some quality instructions to make sure you do it correctly this time.

 

solved it -- it was due to the bumper being removed for maintenance and the lights disconnected and pulled from the bumper sockets. Soon as I put the bumper back on and bulbs back in all the sockets, the brake controller regained full function. I never did solve what the third wire was on the brake switch. But per the wiring diagram the far right wire that gets energized when the pedal is depressed is NOT the main brake light switch - this added info is for the benefit of future readers looking for the same answer regarding the third wire.. I recommend getting into the full wiring diagram to see what it is.