Lotus Elan

Wiring in a horn relay...

PostPost by: billwill » Thu Jul 16, 2015 2:55 pm

Original wiring looms used thicker wire, I think, so the heavier loading worked?

Replacement looms have thinner wire. The thinner wire is used on modern cars as they have many more wires, but also more relays.
Bill Williams

36/6725 S3 Coupe OGU108E Yellow over Black.
billwill
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 4721
Joined: 19 Apr 2008
Location: London UK

PostPost by: l10tus » Thu Jul 16, 2015 3:22 pm

Phil.H,

Sorry, didn't mean to hijack your thread, but Bill's and other replies, were really helpful I thought?

(Thanks, I'll give it a go as recommended.)

Hope you sort your Horn issue out !

Regards,

Phil.T.
Philip.

UK '72 Sprint DHC

Sometimes my Lotus makes me cry.
User avatar
l10tus
Third Gear
Third Gear
 
Posts: 423
Joined: 10 Apr 2008
Location: Shropshire, United Kingdom.

PostPost by: oldchieft » Thu Jul 16, 2015 6:22 pm

oldchieft wrote:
l10tus wrote:Right, now add in the Air Horns !

Anybody suggest a wiring diagram for both sets of horns, so as to sound at the same time (as original?)

I can only get either or to work ( both with relays)

Any ideas, because that's got to be the follow-on to this thread!

Regards,

Phil.


I had a set up on a Morgan were the electric horn worked off the original switch and another push button operated both horns.

(The electric ones always sounds first as the is no compressor to run up to speed. So it give a quick response followed by a loud blast.)

I will try to remember/work out how I did it. I think it might be by cascading two relays.

Jon the Chief


Ok, checked it out, and as suspected it was a cascade set up.

Take a feed from the input side of the fuse box brown wire, put in a inline fuse holder.

Mount an extra horn push and feed it from your new fuse holder, take the output from the new push to the coil of a relay, the other side of the coil earthed.

Feed the COM side of the relay from the new line fuse, take the N.O. side of the relay to the air compressor.

That is the normal set up for extra air horns.

To make the original horns work from the new horn push.

Take a daisy chain wire from the COM terminal of the first relay to the COM terminal on the second relay, take a daisy chain wire from the N.O. output of the first relay to the coil of the second relay, the other side of the coil to earth.

Take a the N.O. from the second relay and feed the original horns at any convenient point in the wiring, but best taken all the way to the horns.

This way the two systems are separated by two open switches, the original horn push and the open relay.

Jon the Chief.
oldchieft
Third Gear
Third Gear
 
Posts: 402
Joined: 17 Sep 2013
Location: Near Wolverhampton

PostPost by: pharriso » Sat Jul 18, 2015 5:05 pm

OK Chaps the weekend is here so managed to install the relay:

I bought a nice small 30a relay off eBay, was originally going to use a more date correct 6RA but too big! Here's it installed:
0260K_WindtonesWithRelay.jpg and
The relay is mounted on the bracket


Here you can see how I interrupted the purple/black wire that goes to the horn push & then rewrapped the loom:
0260K_WindtonesWithRelayWiring.jpg and


& most important of all it works as designed! :D :D :D
Phil Harrison
1972 Elan Sprint 0260K
User avatar
pharriso
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2799
Joined: 15 Sep 2010
Location: Long Island NY, USA

PostPost by: pharriso » Sat Jul 18, 2015 5:18 pm

Finalized wiring diagram:
Attachments
Horn_Wiring_WithRelay_1.02.pdf
(48.95 KiB) Downloaded 246 times
Phil Harrison
1972 Elan Sprint 0260K
User avatar
pharriso
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2799
Joined: 15 Sep 2010
Location: Long Island NY, USA

PostPost by: gjz30075 » Sat Jul 18, 2015 7:12 pm

Phil, does this nullify the first diagram you posted?
Greg Z
45/0243K Sprint
36/5727 pre airflow coupe
User avatar
gjz30075
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2969
Joined: 12 Sep 2003
Location: Roswell, Georgia, USA

PostPost by: pharriso » Sat Jul 18, 2015 9:08 pm

gjz30075 wrote:Phil, does this nullify the first diagram you posted?

I just added a few labels & added the table with relay terminal designations. No functional changes at all!
Phil Harrison
1972 Elan Sprint 0260K
User avatar
pharriso
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2799
Joined: 15 Sep 2010
Location: Long Island NY, USA

PostPost by: oldchieft » Sat Jul 18, 2015 10:40 pm

oldchieft wrote:
oldchieft wrote:
l10tus wrote:Right, now add in the Air Horns !

Anybody suggest a wiring diagram for both sets of horns, so as to sound at the same time (as original?)

I can only get either or to work ( both with relays)

Any ideas, because that's got to be the follow-on to this thread!

Regards,

Phil.


I had a set up on a Morgan were the electric horn worked off the original switch and another push button operated both horns.

(The electric ones always sounds first as the is no compressor to run up to speed. So it give a quick response followed by a loud blast.)

I will try to remember/work out how I did it. I think it might be by cascading two relays.

Jon the Chief


Ok, checked it out, and as suspected it was a cascade set up.

Take a feed from the input side of the fuse box brown wire, put in a inline fuse holder.

Mount an extra horn push and feed it from your new fuse holder, take the output from the new push to the coil of a relay, the other side of the coil earthed.

Feed the COM side of the relay from the new line fuse, take the N.O. side of the relay to the air compressor.

That is the normal set up for extra air horns.

To make the original horns work from the new horn push.

Take a daisy chain wire from the COM terminal of the first relay to the COM terminal on the second relay, take a daisy chain wire from the N.O. output of the first relay to the coil of the second relay, the other side of the coil to earth.

Take a the N.O. from the second relay and feed the original horns at any convenient point in the wiring, but best taken all the way to the horns.

This way the two systems are separated by two open switches, the original horn push and the open relay.

Jon the Chief.


I forgot the Lotus runs the horn wiring back to the steering column then earths it.

To make the original horns work from the new horn push.

Take a wire from the purple and black side of the electric horn to the COM terminal on the second relay, take a wire from the N.O. output of the second relay to earth.

Take a daisy chain wire the N.O. of the first relay and feed the coil of the second relay, other side of the coil to earth.

This should work for Column earth systems.

Jon the Chief
oldchieft
Third Gear
Third Gear
 
Posts: 402
Joined: 17 Sep 2013
Location: Near Wolverhampton
Previous

Total Online:

Users browsing this forum: No registered users and 9 guests