Author Topic: Headlight Wires Mystery - Relay Upgrade  (Read 1272 times)

Offline Roberto

  • Registered User
  • *
  • Posts: 628
  • Location: Adelaide
  • When will 70's sunroofs come back in fashion?
Headlight Wires Mystery - Relay Upgrade
« on: April 16, 2012, 02:12:10 PM »
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 ;D
Roberto
1974 Datsun 260Z
RS30-001060 (2-seater)

Online Scoota G

  • R.O.E.
  • Donating Member
  • Registered User
  • ***
  • Posts: 3696
  • Location: Ballarat
  • Mark
Re: Headlight Wires Mystery - Relay Upgrade
« Reply #1 on: April 16, 2012, 02:24:48 PM »
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!
1975 260Z Triple 45MM Dellortos Daily Driver
1975 260Z 2+2 302 V8 C4 Auto (Shop Build)
1975 Torana SLR 5000 Tribute (shop build)

http://www.facebook.com/home.php#!/StreetWeaponRestorations


Technology costs a money and a money we don't got

Offline Zedman240

  • Dimitri Vazz
  • Global Moderator
  • Registered User
  • *****
  • Posts: 4893
  • Location: Way out SE Melbourne
  • I want your old SHOGUN bike! PM me now...
Re: Headlight Wires Mystery - Relay Upgrade
« Reply #2 on: April 16, 2012, 05:41:13 PM »
Also, male sure all the grounds are attached...and grounding!
HS30-00121 'early girl'
Have u got any old SHOGUN bikes in the shed? Under the house? ME WANT!
Breaks-Something that fails.
Brakes-Stop your car.
There-in  or  at  that  place (opposed  to  here).
Their-of, belonging to, made by, or done by them

Offline Roberto

  • Registered User
  • *
  • Posts: 628
  • Location: Adelaide
  • When will 70's sunroofs come back in fashion?
Re: Headlight Wires Mystery - Relay Upgrade
« Reply #3 on: April 16, 2012, 06:03:44 PM »
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.  :D

I will update this thread when there is an answer.  Cheers
Roberto
1974 Datsun 260Z
RS30-001060 (2-seater)

Offline peter t

  • Donating Member
  • Registered User
  • ***
  • Posts: 1216
  • Location: Logan
Re: Headlight Wires Mystery - Relay Upgrade
« Reply #4 on: April 17, 2012, 03:03:55 PM »
From memory mine was doing the same thing with the test lamp. Wired it up as per Atlantic Z diagram and all works fine.  8)
Official old fart.

Offline Roberto

  • Registered User
  • *
  • Posts: 628
  • Location: Adelaide
  • When will 70's sunroofs come back in fashion?
Re: Headlight Wires Mystery - Relay Upgrade
« Reply #5 on: April 17, 2012, 04:19:46 PM »
From memory mine was doing the same thing with the test lamp. Wired it up as per Atlantic Z diagram and all works fine.  8)

Are you sure??  :o 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? ;D
Roberto
1974 Datsun 260Z
RS30-001060 (2-seater)

Offline NZeder

  • Registered User
  • *
  • Posts: 2203
  • Location: Auckland, NZ
    • http://nzeder.net
Re: Headlight Wires Mystery - Relay Upgrade
« Reply #6 on: April 17, 2012, 07:22:01 PM »
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)
« Last Edit: April 17, 2012, 07:30:58 PM by NZeder »

76 RS30 260z 改RB26 N/A 霞
Previous
70 HS30-00016 240z
72 HS30 240z L型 2.8
71 HS30 240z L型改3.2
79 HS130 280zx
82 HS130 280zx T top
2x 73 KP710 160JSSS
74 KB210 120Y Coupe
71 510 1600 Deluxe

Offline peter t

  • Donating Member
  • Registered User
  • ***
  • Posts: 1216
  • Location: Logan
Re: Headlight Wires Mystery - Relay Upgrade
« Reply #7 on: April 18, 2012, 02:45:48 PM »
Are you sure??  :o 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? ;D
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.  8)
Official old fart.

Offline Roberto

  • Registered User
  • *
  • Posts: 628
  • Location: Adelaide
  • When will 70's sunroofs come back in fashion?
Re: Headlight Wires Mystery - Relay Upgrade
« Reply #8 on: April 19, 2012, 03:55:14 PM »
Mystery Solved:

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

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......
Roberto
1974 Datsun 260Z
RS30-001060 (2-seater)

Offline peter t

  • Donating Member
  • Registered User
  • ***
  • Posts: 1216
  • Location: Logan
Re: Headlight Wires Mystery - Relay Upgrade
« Reply #9 on: April 19, 2012, 04:13:57 PM »
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. 8)
Official old fart.

Auszcar 240z, 260z, 280zx Forums

Re: Headlight Wires Mystery - Relay Upgrade
« Reply #9 on: April 19, 2012, 04:13:57 PM »