Headlamps/lights - died

stanleebates · Post by **stanleebates** » May 15th, 2006, 5:48 pm

Hi all I'm new to this forum but I've been watching it for a year or so and have owned my 1997 MX3 V6 for 6 years now.

I've just encountered a problem with my headlights. They come on when dimmed (side lights) but when you turn the stalk all the way to full, they don't get any brighter. It happened at the same time to both lights. If you pull the stalk up, the full beam activates but not when pushed down.

I've changed the indicator stalk assembly and checked the relay inside the cabin (which still clicks on and off) but I'm not sure where to go next. The bulbs are fine and only a few months old. There appears to be a bank of 4 relays just inside the bonnet/hood and a small sticker showing a dipped headlight and 1.3%.

I don't know what to check next and the dealer can't help (he thought it was the indicator stalk).

Grants · Post by **Grants** » May 16th, 2006, 8:35 am

There appears to be a bank of 4 relays just inside the bonnet/hood

They're for the a/c, fans, etc.

The headlights only have 1 relay which is under the dash.

The diagram is here:
http://eunos30x.com/info/1995%20Wiring%20Diagrams.pdf
Page 16.

Looks to me like it can't be anything BUT the switch. If it works in one direction (up) but not the other.....

When you say you replaced the "stalk assembly", did you replace the WHOLE thing? The "dimmer" switch on the diagram must be mechanical so its almost certainly must be that.

* Look on the diagram, inside the dotted box labelled "light dimmer switch (combination switch)". Ok, see the RED / WHITE wire coming up from the headlight into the switch? Thats high beam. It can get power from 2 places - the "flash to pass" or "dimmer". Can't see how one works but not the other unless its something mechanical that operates that "dimmer switch". Hope thats clear enough, good luck with it.

stanleebates · Post by **stanleebates** » May 16th, 2006, 6:19 pm

Thanks Grants, yes I replaced the whole assembly, and its still exactly the same problem as before. The thing is, I can hear the relay click when the main beam is selected on the stalk, but nothing happens. I'll have a look at the diagram in slow time and get back to you if I may - its so frustrating when you've taken the airbag, steering wheel and clock off to get to it only to find it still doesn't work, and they're hardly cheap - it costs over £200 here just for the part!

ariesdude · Post by **ariesdude** » May 16th, 2006, 6:46 pm

If you have a tester or multimeter it will be easy to test if the relay is getting +12v and putting out +12v. If the relay is ok then it could be the wiring from the relay to the headlamp assembly (assuming your bulbs are the correct rating and working fine).

Grants · Post by **Grants** » May 16th, 2006, 8:04 pm

Hang on...

They come on when dimmed (side lights) but when you turn the stalk all the way to full, they don't get any brighter.

The thing is, I can hear the relay click when the main beam is selected on the stalk, but nothing happens.

Those 2 comments seem to be at odds with each other.

Can you please confirm exactly what happens, with the stalk in the middle position, when:
- you select parkers (one click)
- you select headlights (2 clicks)
- you select high beam (push stalk forward)
- you operate "flash to pass" (pull stalk back).

I thought you meant it operates in headlights ok but can't select high beam. If you can confirm exactly whats happening we can have another look at it.

Cheers

stanleebates · Post by **stanleebates** » May 20th, 2006, 8:43 am

Hiya Grants, in answer to your questions, please see below:

- you select parkers (one click) Parking lights come on
- you select headlights (2 clicks) Parking lights stay on and relay clicks but nothing else happens
- you select high beam (push stalk forward) Parking lights stay on but nothing else happens
- you operate "flash to pass" (pull stalk back). Full Beam Flash comes on

Many thanks for helping with this.

Grants · Post by **Grants** » May 20th, 2006, 11:08 am

(The parkers are a whole different circuit so they work independently.)

The "flash to pass" bypasses the headlight relay so I'd suggest swapping the headlight relay for a test. Grab one of those in the engine bay near the firewall for this test purpose. The plug will be the same. Don't start removing things, just plug the new relay in...

It won't be the fuse if that high beam mode works, so try that - just cause you hear the relay "click" doesn't mean its making electrical contact.

If this doesn't work, you got a hard wiring fault, which I doubt. 99% of faults are in movable parts so my monies on the relay. Let us know

stanleebates · Post by **stanleebates** » May 20th, 2006, 12:21 pm

Hi Grants, thanks for that. Just been out there with my multimeter and your wiring diagram.

It seems that the relay I was looking at was the TNS (Tail 'n' Side?) relay - it comes ON when side lights are selected and OFF when headlights are selected which seems about right.

I looked at your diagram again and it says that the Headlight relay is on the left side of I/P - bearing in mind that my MX3 is a right hand drive I tried looking to the right side of my I/P (behind the wheel) - there was another relay there - exactly the same as the TNS relay on the far left of the car by the kick panel - I switched them over but it produced exactly the same response unfortunately.

To that end it may be that I haven't actually located the headlight relay itself yet. There are 3 relays on the left of the car (left of passenger footwell) and two underneath the steering wheel (the TNS-like relay and a small 10A relay) none of which seem to change voltage on any input pin when selecting headlights. As you say, if the TNS relay changes state when headlights are selected, it can't be this relay or the indicator stalk assembly, so the only thing left is the headlight relay itself.

Any ideas?

Grants · Post by **Grants** » May 20th, 2006, 2:07 pm

If you've got a TNS relay, it should stay activated throughout your lighting selection. It acivates on parkers and stays activated for low / high beam too (but is independant of the headlight circuit).

AU spec (RHD) doesn't have a TNS relay or headlight relay. Its all done via direct switching.

Forget the relay in the LHS kick panel - its not lighting, (but I think you knew that and just went with a test?).

If there's only a couple under the dash you may find you're in the same boat as us - no diagrams available. Could be your switch? Likely; mine went down and needed a good swim in WD40 to come back again. But that swim worked, been good for the last 2 years with it.

Lemme think about it. Its not the switch, there may not be a relay, but its 4:05AM so I'm not much good at the moment....

stanleebates · Post by **stanleebates** » May 22nd, 2006, 4:31 pm

Hiya Grant, the story so far:

I've tested the indicator stalk - 3 simple wires on a switch - they correctly power up when the relevant positions are selected but are too small to power anything more than a relay.

I've found a relay that clicks when the switch is turned full on - but has no effect on the lights. I tested it and it makes contact when the headlights are selected.

I can hear another relay under the hood/bonnet clicking, but can't find it and think that is the exterior lighting circuit (TNS) relay.

There must be something we're missing here but I can't find it. I've ordered a Mazda workshop manual on CD off ebay and am considering getting a chilton manual from USA to see if there's anything in them - but to be honest I'm about an inch away from taking it back to the garage - something I want to avoid at £85 an hour!

If you have any ideas, I will welcome them.

Cheers, and thanks for your help so far.

Grants · Post by **Grants** » May 23rd, 2006, 2:09 am

It almost HAS to be the headlight relay.

I've found a relay that clicks when the switch is turned full on - but has no effect on the lights. I tested it and it makes contact when the headlights are selected.

Have you swapped this relay? It may read with a multimeter that it has contact no load), try a voltage reading on both sides of the contact.

There seems to be nothing wrong on the TNS side, it should just energise and stay energised with either "parkers" or "headlights" selected.