Wiring in factory tell tail for trailer

Post anything electrical or ICE here. ie, upgrading your stereo, or removing looms etc.

Moderator: Octane2097

User avatar
diggerhole
CB-Uk User
Posts: 412
Joined: Sun Feb 03, 2013 12:46 am

Wiring in factory tell tail for trailer

Post by diggerhole » Sat Aug 09, 2014 6:05 pm

As I slowly improve my van I am trying to add as many factory options as I can.

One of the items i wanted was the factory trailer tell tail to work

Image

This lights up when a trailer is connected and the indicators are working. Much nicer than a buzzer.

Things you need.

Dash connector from donor car for contact
Image
New dash bulb
Uninsulated spade
Butt connection
50cm of wire
Image

Last you need a new relay to replace the 3 pin flasher with a 4 pin with a c2 connector on it.

Image
Image

So dash out. Add the new contact to the dash connector at position 26. Insert bulb in space 9 on board then run the wire down to the fuse box and put the new spade in the top empty slot to connect to c2 where the relay came out.

Put new relay in and tell tail now works

You will need to drop the fuse box, remove the dash and take the drivers vent out. But in all honesty a hours spannering.

Hope this helps others.

User avatar
diggerhole
CB-Uk User
Posts: 412
Joined: Sun Feb 03, 2013 12:46 am

Re: Wiring in factory tell tail for trailer

Post by diggerhole » Sat Aug 09, 2014 6:08 pm

The tell tail will flash with hazards but only flash once with no trailer
More info here

http://workshop-manuals.com/vauxhall/co ... _73_78_79/

Deedee91
CB-Uk User
Posts: 494
Joined: Mon Jul 21, 2014 10:28 pm

Re: Wiring in factory tell tail for trailer

Post by Deedee91 » Sat Jul 11, 2015 1:46 pm

How does the tell tale know a trailer is connected?

Just fitted a tow bar looking at wiring it up now got a few extra bits to do this as well.

When u say dash out do you mean the dashboard or instrument cluster btw? Ha

User avatar
johnny
Senior Moderator
Posts: 4875
Joined: Sun Jul 08, 2012 3:26 am
Location: Donegal,Ireland

Re: Wiring in factory tell tail for trailer

Post by johnny » Sat Jul 11, 2015 4:52 pm

Not 100% but fairly sure it works off the completed circuit of the trailer plug so when there's a socket in the plug the circuit gets completed and the light illuminates
If it doesn't fit,
force it,
If it breaks,
It needed replacing anyway :thumbs:

Deedee91
CB-Uk User
Posts: 494
Joined: Mon Jul 21, 2014 10:28 pm

Re: Wiring in factory tell tail for trailer

Post by Deedee91 » Sat Jul 11, 2015 6:13 pm

johnny wrote:Not 100% but fairly sure it works off the completed circuit of the trailer plug so when there's a socket in the plug the circuit gets completed and the light illuminates


I thought this but the trailer plug is just spliced into the wiring in the back light for indicators etc.. There's no physical connection between the relay and the trailer plug. Although I might be missing something obvious :lol:

User avatar
diggerhole
CB-Uk User
Posts: 412
Joined: Sun Feb 03, 2013 12:46 am

Re: Wiring in factory tell tail for trailer

Post by diggerhole » Sun Jul 12, 2015 11:56 am

The extra bit is the relay with a C2 pin and a wire from that pin to the dash bulb. The relay works by sending a signal from C2 when sensing extra load. The additional tell tail will show when hazards used or flash once when indicating without a trailer. With trailer The extra load makes it light up all the time. Simples

Sent from my SM-N9005 using Tapatalk

User avatar
diggerhole
CB-Uk User
Posts: 412
Joined: Sun Feb 03, 2013 12:46 am

Re: Wiring in factory tell tail for trailer

Post by diggerhole » Sun Jul 12, 2015 11:59 am

Just to note. Other vauxhalls use different methods. For example the fonteria has an extra loom and relay.

Sent from my SM-N9005 using Tapatalk

User avatar
diggerhole
CB-Uk User
Posts: 412
Joined: Sun Feb 03, 2013 12:46 am

Re: Wiring in factory tell tail for trailer

Post by diggerhole » Sun Jul 12, 2015 12:00 pm

Deedee91 wrote:How does the tell tale know a trailer is connected?

Just fitted a tow bar looking at wiring it up now got a few extra bits to do this as well.

When u say dash out do you mean the dashboard or instrument cluster btw? Ha
Just the instrument cluster [emoji3]

Sent from my SM-N9005 using Tapatalk

Deedee91
CB-Uk User
Posts: 494
Joined: Mon Jul 21, 2014 10:28 pm

Re: Wiring in factory tell tail for trailer

Post by Deedee91 » Sun Jul 12, 2015 2:49 pm

diggerhole wrote:The extra bit is the relay with a C2 pin and a wire from that pin to the dash bulb. The relay works by sending a signal from C2 when sensing extra load. The additional tell tail will show when hazards used or flash once when indicating without a trailer. With trailer The extra load makes it light up all the time. Simples

Sent from my SM-N9005 using Tapatalk
Excellent, thanks very much.

I had come up with all sorts of random ways it could work in my head.

Always the simple ways.

We're you a Vauxhall mechanic at some point?

User avatar
diggerhole
CB-Uk User
Posts: 412
Joined: Sun Feb 03, 2013 12:46 am

Re: Wiring in factory tell tail for trailer

Post by diggerhole » Sun Jul 12, 2015 2:53 pm

Deedee91 wrote:
diggerhole wrote:The extra bit is the relay with a C2 pin and a wire from that pin to the dash bulb. The relay works by sending a signal from C2 when sensing extra load. The additional tell tail will show when hazards used or flash once when indicating without a trailer. With trailer The extra load makes it light up all the time. Simples

Sent from my SM-N9005 using Tapatalk
Excellent, thanks very much.

I had come up with all sorts of random ways it could work in my head.

Always the simple ways.

We're you a Vauxhall mechanic at some point?
Nope, just a proffesional bodger with access to workshop manuals. [emoji16].

Sent from my SM-N9005 using Tapatalk

User avatar
diggerhole
CB-Uk User
Posts: 412
Joined: Sun Feb 03, 2013 12:46 am

Re: Wiring in factory tell tail for trailer

Post by diggerhole » Fri Jul 17, 2015 11:14 am

https://en.m.wikipedia.org/wiki/DIN_72552

Sent from my SM-N9005 using Tapatalk