Headlight Wires Mystery - Relay Upgrade

[Roberto]

This one has plagued me for more than 10 years and i have never been able to have high and low beams work. It's either one or the other depending on how i hooked up the relays.  I will beat it now if it kills me, so can someone please help!!

The 3 wires of interest that are used to connect to the relays for headlight upgrade are R, RW (low beam earth) and RB (high beam earth). Simple, right?

The mystery is why I am getting power (with test light) through the R but also RW wire with low beam??  This should not be happening and stops me from correctly hooking everything up.

This is more serious than an inspection lamp

[Scoota G]

Maybe it is or maybe the two problems are both connected. Damage to the radiator part of the loom could be causing both. Also check to make sure you have the headlights on the correct side!

[Zedman240®]

Also, male sure all the grounds are attached...and grounding!

[Roberto]

Good advice boys.   

Well, i spoke to an auto electrician this afternoon who also owns 2 zeds and does many relay upgrades for zeds and he does believe something is sinister.  No power should be going through the RW wire and if so, something has shorted out and this should be addressed.  He said when the car is drivable to bring it to his worshop and he will sort this out.  He will also look into the inspection lamp mystery too. 

I will update this thread when there is an answer.  Cheers

[peter t]

From memory mine was doing the same thing with the test lamp. Wired it up as per Atlantic Z diagram and all works fine. 

[Roberto]

From memory mine was doing the same thing with the test lamp. Wired it up as per Atlantic Z diagram and all works fine. 

Are you sure??  Do you remember if the RB showed current too?  Mine doesn't as one would expect for an earth. But if the RW shows current and the R has current, how do these two wires switch the relay on??

Is it a big hassle to double check Peter?

[NZeder]

You know zed are wired a bit different in the headlight department. The fuses are for lh and rh not hi low like most expect. And the switch connects the earth to the circuit. So if someone has done a relay conversion and did not do one of the following you can have issues.

1. Take the factory setup in consideration and place the relays in the correct location in the circuit.
2. Rewire the headlight and switch to suit the required relay design.

I have included a screenshot of the Atlantic Z pdf show one way of doing it. This changes the headlight from having the centre tap connected to power and switching the earth to having the centre tap connected to earth and via the relay connecting the power.

One more thing is your switch working correctly. The issue with the zed setup  is the switch sees the full current as it makes the connection to ground and closes the circuit. It is for this reason most install relays. Do you want all the current so close to you or the steering column (the earthing medium in the case)

[peter t]

Are you sure??  Do you remember if the RB showed current too?  Mine doesn't as one would expect for an earth. But if the RW shows current and the R has current, how do these two wires switch the relay on??

Is it a big hassle to double check Peter?

All taped up now so it is a bit hard to check but if you take NZeder's advice and mine and wire up as per the supplied diagram there shouldn't be a problem unless your switches are already fried. Remember once the light switch is turned on the dimmer is earthing not suppling power. 

[Roberto]

Mystery Solved:

I hooked it up according to this wiring diagram (cheers Benny) and presto it works correctly, high and low beams!

What was confusing me was the power to the RW wire with low beam.  It doesn't matter since this wire gets earthed when high beams are on and hence that activates the relay for high beams.

I shouldn't have been thinking and testing wires with test lamps......

[peter t]

Thats great mate. I had Benny's diagram as well but was confused as it is totally different to the Atlantic diagram as to what wires go to what terminals on the relays. Main thing you have lights and I have lights.