evilstuie

Hi Guys,
I've found it just about impossible to track down any more of the headlight door motor actuator relays from here in Australia. I've tried the 2-3 different GM numbers on ebay and everywhere I'd be able to order them from and either they don't exist or people want $50-80 for a relay.

I've read on the forums here a lot of people just rewire in standard SPDT automotive relays to handle the job, but no-one ever mentions the specifics of it.

According to the wiring diagram for the stock relays, the wires go as such:
Pink/White - 12volt hot at all times
Black - Ground
Pink - Isolation Relay
DarkGreen/white -Headlight motor (B)
Grey/Black - Headlight motor (A)

Now from what I can see and guess to so far the SPDT relay(5pin) should go like this:
30- 12volt hot at all times
85- Isolation relay (to switch on/off)
86- Ground
87- Headlight motor (A/B)
87a- Headlight motor (opposite of above)

I'm going to tinker this afternoon, but if anyone could confirm these before I start it may save me a lot of hassles and fuses.

Also if someone would like to add the specifics and diagram for making the isolation relay from the 2 SPDT relays and diode to the post it'd be a nice quick reference point for people needing to fix this bastard of a problem that seems to affect everyone.

Also if anyone knows the amp rating for the relays that should be used, that would help also. I've got a bunch of 50amp ones I was going to use, but was wondering if 80amp ones off ebay for $4 would be more reliable, or if they'd cause issues?

TreeFiddy

Ok Stuie. Attached here are the original factory circuit, and my proposed fix.

The iso relay is replaced with a single SPDT standard auto relay. As far as I can tell, the only isolating the factory iso circuit does is cut the open/close signal power to the actuator relays when the headlight switch is in park. I don't know what this is actually supposed to achieve; my circuit changes the iso relay function to a simple open/close signal, with no park isolate.

I've had my iso relay replaced like this for many years now, no issues.

Next, I propose to replace the DPDT actuator relays, by simulating them with 2 x SPDT standard auto relays wired in parallel. I haven't actually done this myself, but don't see why it wouldn't work - it should supply the same polarity reverse to the door motors as the stock relays.

evilstuie

I'll try it this afternoon and see what happens

LX_SS

The purpose of the isolation relay is that you can raise you headlights and switch back to park to stop the movement, i.e. get it in the right spot and change a headlamp globe.
So using a spdt relay, you would have trouble changing headlamp globes vs a proper dpdt relays


You also need to add some diodes as well to stop feedback loops.

http://www.jaycar.com.au/productView.asp?ID=SY4065

That will do the job for the relay, you will need x 3 of them, the internal circuit breaker of each headlamp motor is 10a, so 50a/80a relays is stupid overkill.

evilstuie

So I only need 3 of these plus a diode to replace all GM relays for the headlight motors?
Instead of wiring up 2 SPDT relays?

LX_SS

well, if you do entire spdt relays there are 2 on each headlight, plus 1 for the iso, so thats 5 x spdt relays.

If you use dpdt relays, you need 1 per headlight, 1 for iso, so 3 relays total like factory.

Shoot us a pm with ya email and i'll send you the circuit board diagram using those aftermarket dpdt relays

evilstuie

No problems, just rang Jaycar and they've got 5 in stock so I'll grab all of them encase I stuff it up.

I might just buy a small enclosure too and glue the relays in place to make the wiring a bit neater and secure it to the side of the engine bay.
I've also got a Bi-xenon ballast light setup i was going to put in but wasn't confident of drilling the holes out of the factory light enclosures to put them in, maybe a can give it all a try today

TreeFiddy

I've read that, but never discovered how you were supposed to 'switch back to park' once the headlights were up. You can only go from lights on back to full off. I've never found a need for this function, except to change the lamps once I simply pulled the relay.

Diode not required with the 'isolate' function removed. Like I said, mine's worked fine for many years.

yes of course that will do the job, but the object of this excercise was to use the commonly available auto relays that Stuie said he had plenty of lying around.

evilstuie

The idea of not having to wire in an extra diode appeals to my lazy nature, so I'm happy about that, the $7 relays from Jaycar also appeal to not having to wire extra stuff, so hopefully I can just cut the connectors off the current setup and wire to the DPDT relays and be done with it.
I feel I need to duck down in the Magna to hide from shame so I want to get this going ASAP

TreeFiddy

I'd be concerned with the pcb relay holding up to the under-bonnet conditions (heat, water etc) - I'd definitely enclose them - a good reason for sticking with the 'stupid overkill' auto relays - bulletproof and easy to mount - if only there was a DPDT version

So simpler to wire the correct DPDT type, or simpler to mount 2 x SPDT - choose your lazy option

evilstuie

Haha yeah, I might do a little shopping at JayCar and see if I can rig some sort connector for the relays so if they go again I don't have to unsolder/solder the new ones on again.

LX_SS, if you can email that diagram for the Jaycar ones that'd be awesome

LX_SS

the overkill was 50a/80a relays, your normal common 15/20a 5 pin spst auto relay is fine, you just use/need more.
sent you the circuit design anyway, should be enough for you to wire the relays up.

TreeFiddy

Who said anything about 50-80A relays?? I was referring to the common garden variety 5-pin type that is available cheap in shops everywhere, or free in wreckers everywhere. Cant step sideways without tripping over them

LX_SS

hence overkill, dramatically

TreeFiddy

Ah yeh, back in the first post . But he's got the 50A ones already, so no cost to him, might as well use them. Anyhooo...

LX - can you post your DPDT circuit up here. Replacing these factory relays seems to be a somewhat of an issue here on TGO, which nobody has ever posted a solution to afaik. I've offered a low cost solution which is a little awkward electrically, your's is better electrically but a probably a little more work mounting the relays reliably. Be good to have both options up here.

Sorry jumping in yr thread Stuie, just seen this early relays issue come up a lot before. Let us know how u went

evilstuie

Haha yeah, the more options the better.
Unfortunately I stopped at the pub on the way home and accidently won $2 grand on the pokies so there was a delay in getting to JayCar on time :P
I'll head in tomorrow and get the bits I need hopefully avoiding the pub

evilstuie

Well...

The good news is the diagram you gave me TreeFiddy for the dual SPDT relays and iso relay worked perfect.
I sat down all afternoon, carefully soldering all the points together and clustering the relays 3 on the RHS and 2 on the LHS, then cut the wires from the factory harness one by one twisted, soldered, heatshrinked and electrical taped.

Did the RH side first with the isolation relay, light goes up, light goes down, but nothing on the LH side. Looked at the isolation wires, and there was a bright blue wire, and a darkblue/white wire. I touched the darkblue/white wire to the blue wire and the LH light went down, but wouldn't go up with the factory relay.
Checked it out and the pink white wasn't getting 12volts when the lights were switched.
Also noticed it wasn't used on the dual-spdt setup.

So.... replaced all the left side, and then got to the last wire and realised it needed to go across to the other relay. Grabbed a piece of wire, joined them and hooray!!!
Both lights go up and down, turn on and off and isolate.

I'd only twisted the joining wire together and was looking for a place to route it out of the way before soldering and noticed the relay/brightblue/drkblue&white wires hadn't been soldered. Also wondered if I needed the drkblue/white wire, so i undid it, and tested it, headlight wouldn't go down. Ok i needed it, went to twist the wires back together to check it all still worked.....
And what did i do, wired the dark blue white to the LH relay, vice versa.

The motor started to move then there was a pop, a fizz, some smoke coming from what looked like either the motor or the headlight harness, and I quickly yanked the wire and flicked the switch off.

It's now too dark to see and I'll b e driving the mitzashitti to work again tomorrow.

Any ideas what I've done?
Both headlights still light up, but both motors dont respond up or down. It looks like the iso relay is still working.

evilstuie

Some good news I hope, there's no 12volt going to any of the relay wires or original 12volt sources, so with a LOT of luck maybe I just melted some insulation (smoke and fizz) and blew a fuse on the fuse block.

It's too cold and dark to check the fuses now as I've removed all internal lights, and the fuse panel is only accessible by removing the stereo at the moment as I put a VY commodore fuse block in when I updated the wiring and haven't decided where it's gonna go yet.

Once I get power back there's 3 things I guess it can be:
Fried 1/both motors
Fried the relays
Fried the headlight wire harness
(or fourth option, all of the above)

evilstuie

Eureka Fez! Eureka!!!!!

I'd get bitchslapped by many on the forums, and would be tempted to bitchslap myself for the temporary wiring I put from the battery to the relays to bypass the dead 12v from the factory relay harness, but it goes!!!
I couldn't follow the original wires to the fuse, but I checked all fuses on the fuse panel and they were fine, so it must be an inline one.

But headlights up,down, on off, and work fine, my 200amp alternator is charging nicely and if I have enough fuel to make it to the servo tomorrow, i'll be driving to work in style once more.

evilstuie

Ok, now it's all properly done.
TreeFiddy's diagram works perfectly.
Easiest way is to solder the relay packs together as per the diagram, and then splice into the current harness. Only issue I had was not connecting both blue and dark blue wires together with the trigger wire.
You should be left with a pink white and white wire left over if memory serves.

Now I just need to figure out how to stop the right headlight from shaking when I drive. Has just enough play in it to **** off whoevers in front of my on the road.

evilstuie

On the off chance anyone is monitoring this thread still, my new project is coming to an end and I'm using a different dash with a headlight switch similar to a G8 which is not designed for headlight motors.

The 85 headlights need a yellow and white wire to the isolation relay, I'm pretty sure yellow is lights and white is headlight motors...

If I wire both of these wires to the trigger wire on the non-door switch, would this work?

I.E. The headlight switch wire is wired to both the yellow and white wires on the isolation relay to trigger both when the lights are turned on, or is one 12v and the other ground?