Tekonsha P3 "short To Battery" warning

[mike7]

HI everyone,

Ive just had a Tekonsha P3 fitted to my Disco 4 and am getting a "Warning, Short to battery, no brakes" warning. I had this controller in another car and it worked fine with the same caravan connected.

Was hoping someone has seen this message on the P3 and might have a solution. Thanks in advance.

Cheers
Mike

[Graeme]

Its not wired correctly. The wire going to the brakes is connected to power somewhere, possibly to the brake light circuit.

[mike7]

My appologies I should have given you guys more info after reading what I posted.

When he P3 is not connected to the caravan the unit works as advertised, ie no warnings etc, it's only when I connect it to the caravan that I see the message.

From this I'm thinking to the unit is wired up correctly to the car and the problem in somewhere in the caravan 7 pin plug????? we have had a bit of rain here in the last few days so maybe water in the plug?

Any thoughts appreciated.

Cheers
Mike

[Graeme]

Water in a plug wont provide enough current to make the P3 think the brake wire is connected to power.

With the van not connected, turn on the parker lights and see if the P3 has anythig to say - perhaps the short to battery msg. The D4 wiring needs to have a wire cut in the trailer plug loom when fitting an electric brake controller because it uses pin 5 of the plug as the trailer/van's right tail light whereas in Oz pin 5 is used as the elctric brake wire.

[disco4now]

Hi Mike,
Is this the same trailer/van that your other post about the indicator light not picking up on the dash refers to? Could be related if same trailer/van.
My theory would be that the link between pin 5 (electric brakes) and the tail lights is still in place.( landrover has two feeds to tail lights as standard). The one on pin 5 is not used for australia but needs to removed so pin 5 can be used for the brakes.(see other post on here about cutting the wire)
With trailer unplugged do you get error on P3 controller if lights are on? If so would indicate the link in still there?.
If you swap the indicator bulbs left to right, right to left, does the other fault stay the same of follow the bulb.
When hooked up is the fault on P3 straight away or do you need lights on?

Regards
Gerry

[disco4now]

i type too slow!

[mike7]

G'day guys,

The unit was installed by a LR dealership but was outsourced to their electricians so Im assuming the job was done right. the van was done by jayco when I had another car with the same P3 and it worked fine. I removed the P3 and had it installed in the D4 and this is my first time connecting the van to the D4.

Graeme the P3 behaves normally with the park lights on, ie the logo/help screens all display.

Gerry this is another van and not the one in my other post. You guys have mentioned that pin 5 needs to be removed, Ill have a look at this tomorrow morning.

The fault message only appears when I plug the van in, I can see the P3 thinking for a sec and the normal screen that you see with a successful connection pops up for a fraction of a second and then I get the fault message.

What needs to be done with pin 5? Do I simply remove it or do I need to wire the brakes thru it?

Thanks for your help guys, much appreciated.

Cheers
Mike

[Graeme]

Pin 5 needs to be the van brake wire. I suspect the van's plug wiring was changed to match your earlier vehicle and is not currently using pin 5 as the brake wire.

[mike7]

HI Graeme,

Ive pulled the plug apart and it looks like from the trailer end pin 5 is the brake, ie blue wire.

You guys have mentioned that pin 5 wire has to be cut, is this at the car end? Im assuming thats somewhere in the wiring loom under the dash.
Cheers
Mike

[Graeme]

Have a look at this thread http://www.aulro.com/afvb/d3-d4-rrs/97935-d4-electric-trailer-brakes.html. The wire to be cut is behind/below the left tail-light cluster.

[Nomad9]

Hi Mike,
Not sure if this is any value but when I put my P3 on my D3 I had to wire the brake connection up to the brake light wire in the nearside rear of the vehicle where the tow hitch wiring is, the brake pedal wires don't or in my case didn't work. I had the same message. Mine now works a treat.

[mike7]

Thanks Graeme and Nomad, I'll check out your suggestions.

Cheers
Mike

[Davehoos]

to fix most of the modern light issues use a 13 pin plug-these are wired so that you can tow a 7 pin box trailer putting the brakes out of the way on pin 12and a decent battery+/- pin...i saw a round 13 pin convetors recently with 12-24 combined systems.

most of the new cars that can tow 2 ton will have to change over to these to operater the electric trailer brake battery rear fog lights and the very rare trailers that have reverse lights or camera.

is the short something stupid like---black is suposed to be power and white is earth.or you have conected to wiring at the stop lights.
to us 40+ old australian mechanic this has tacken some time to get used to and why do they have to complicate simple stuff.[red is stop light positive trigger-and blue is brakes on basic units trailer units]

It was bad enough when brown could be +battery+aux,-earth or parking lights..

I normally been running the stop trigger to the trailer plug .that way you run 2 twin cores wires on to battery supply/earth the other to trailer plug.this also helps when you working with 24V stuff.Ive always had problems withwork trucks only operation one stop light of the electric or air trailer brakes.

the stop lights must apply when you use the manual control.most cars today cant cope with the stop/tail light bulb fail system issues-if its conected to the trailer plug stop light contact at least the trailer stop lights work.

[Davehoos]

my trailer was made 1993.
this year at work someone dug out a NSW rego inspection notice.
we do our own rego with random audits-and what this was for to inform about the change to present trailers with assighned tow vehicles the same as motor homes and towed cars.

after 2007 all trailers over 2 ton gross must have electric brakes with a brakeaway system that charges of the towed vehicle and has a warning system to indicate the charge condition.they requied the battery to last 15 minutes.mine had a N70 that would last over night.

the electric brake earth return must not use the chasis earth system---it actually states that earth must not pass throuh mechanical components.
that migh be you could use twin core from from the brake drum/hydrolic control to the chasis-then-chasis to trailer battery and trailer plug battery earth return.

I would sudjest that the white earth wire in 7 pin plug not be used as it for light systems.my trailer had another loose wire that i misstook for the battery charge aux wire being red and it caught fire in the circuit braker.

[mike7]

Problem now solved, wire had to be snipped. Looks like the dealership didn't do the install properly.

Gentlemen my sincerest thanks for all your help with this.

Cheers
Mike

[tempestv8]

Hi Mike,

Happy New Year to you.

Can you reiterate - which colour wire had to be snipped, and I assume you meant that this wire is that off the wiring loom on the vehicle, not the caravan?

[mike7]

Gday Tempest,

My apologies for the late reply but have just got back from holidays.

I dont remember which wire he cut but it was in the wiring loom in the left tail light assembly as per the posts here talking about trailer led lights.

The brake controller was seeing power when the car headlights were turned on. Sorry I know its a vague answer but it had something to do with the european cars having a dual tail light circuit or something like that. I didnt understand fully what the problem was but there were a couple of faults with the installation by the dealer.

Cheers
Mike

[101RRS]

As wired the Discos have separate power to left and right taillights. The Aust system has one power feed to both tail lights. If left unmodified, one of the tail light feeds to the trailer brakes (due to the Aust trailer wiring system) and the other tail light feed supplies power to both tail lights.

In my RRS I have not snipped any wires as yet - just pulled the fuse in the rear compartment fuse box that feeds to the trailer brakes - when I put my controller in I will snip the input wire on this fuse and connect the wire that activates the trailer brakes there with the fuse back in place.

Garry