Tow bar electrics

stewd · Sep 12, 2016

Hi all,

My trailer warning light on the dash has never worked so over the weekend I thought I'd see if it was fixable, the bulb is fine and there is wires going to it so couldn't see anything wrong.

looking at the trailer wires the trailer socket is just plugged straight into the back lights (indicators / breaks / sides etc..) and an earth taken from one of the lights, (all connected with bullet connectors).

There is a 7 core cable coming up through the floor with all the right trailer light colours on the wires but isn't connected to anything, should this also be patched in to the trailer loom to "talk" to the trailer warning light?

Is a 300tdi 110 - 1994
Thanks

Al2O3 · Sep 12, 2016

How is the trailer socket wired in to the back lights? I cant picture that.
The cables coming out of the drivers side wheel arch in the tub should connect to another harness that goes back down through the wheel arch to a female connector by the tow bar. The male connector, from the trailer, then connects in to this. Only through the correct harness will the trailer indicator light work on the dash.

Kwakerman · Sep 13, 2016

On mine (1996 300 90 CSW) the cable from the towbar socket goes up in to the tub behind the small triangular cover just above the rear door check strap. Under that cover there is a bunch of bullet connectors where the towbar socket cable joins with the main loom. FYI the trailer light should flash once each time you use the indicators (unless you have fitted LED indicators and associated relay)

MeatCleaverX86 · Sep 13, 2016

If all you lights and trailers lights are working and only the Trailer / indicator bulb doesn't illuminate its a good chance you need upgrade the indicator relay.

the trailer dash light should flash once when indicating with no no trailer on the back if this doesn't happen i bet money on the relay to blame there is an additional pin on the trailer one. this is was the case on my 94 def 90

the dash light is triggered by the extra current draw of tailer lights

stewd · Sep 13, 2016

]Hi,
I have the bullet connectors it look likes the socket just comes from these, the attached picture might help a little bit,

Richard - that makes sense if it just works on the extra power draw, the light doesn't flash even if I don't have a trailer attached, I will check the relay.

stewd · Sep 13, 2016

Also forgot to add. Some times my indicators don't come on, pressing the hazard switch fixes this (been meaning to replace the switch for ages) could this be the cause?

Al2O3 · Sep 13, 2016

It's the set of cables at the back of your picture. As you'll know the nearer ones go to the door switch, heated rear screen and rear wiper.
here's a shot of mine

This is the wiring codes, for mine anyway.

1996%20Defender%20300Tdi%20Trailer%20Wiring%20Diagram_zps0oytqexd.jpg

Tow bar electrics

stewd

Active Member

Al2O3

Well-Known Member

Kwakerman

Well-Known Member

MeatCleaverX86

Active Member

stewd

Active Member

Attachments

stewd

Active Member

Al2O3

Well-Known Member

Similar threads