high beam not working
 

when i flick the high beam switch the headlights stay on low beam and one of the relays near the front of the engine bay begins buzzing until i flick the high beam switch again.
I've tried replacing the relay with a brand new one but it did the same thing.
the blue high beam light on the dash stays constantly illuminated when i flick the high
beam switch on and off. what could the problem be?

What series and more specifically year car. If it's an s4, it's most likely your headlight switch needs resoldering or just get a new one. If this is an s5 or s5 vert for the matter it gets a bit complicated.

It's a series 4, 1986. Doesn't the fact that the relay buzzes when i flick
the high beam switch indicate that the switch is working?

A buzzing relay could mean it is not getting the proper current. By headlight switch I mean the switch located on the dash itself to turn the headlight Up and On, not the turn signal switch/high beam switch. They are known to get cold solder joints and eventually burn out your headlight harness if not properly fixed. What you are experience is probably due to a short in the switch itself, because of the solder joints, which is causing a "buzz". Take it out and either have someone or you resolder all the contacts on it or get one that doesn't have this problem.

Another thing, check the electrical harness to the headlights. There could be corrosion causing this problem too...

If you search for headlight switch you should find some information on rebuilding it.

All the headlight switch itself does, is put a ground on the headlight RELAY which has power on it 24/7.

Selecting high/low beam is done with the Dimmer Switch (lever outfit).

So you select to turn the headlights on with the headlight switch. It puts a gnd (Blue line) on the Headlight Relay's coil (negative side) and also to the Dimmer switch . Headlight relay pulls in and sends power (pink line) to a set of contact in the Dimmer Relay and also to the positive side of the Dimmer Relays coil. Power passed thru the Dimmer Relay and goes to the headlight filiments.

Now you select High beams with the lever. That puts a gnd on the Dimmer relays coil (negative side of the coil that already has pwr on the positive side). The dimmer relay pulls in and the power now flow from the other wire on the dimmer relays plug (purple).

Chattering relays can be caused by the pwr to its coil coming and going rapidly or the ground to the coil coming and going rapidly.

Personally I'd turn the headlights on. The go to the Dimmer Relay. With a piece of wire bare at each end, I'd put one end of that wire to a known gnd point and the other end I'd backprobe the WHITE wire in the dimmer relays base (all things still connected together, nothing taken apart). When you do that the headlights should stay on high beam steady.

IF the chattering goes away, I'd suspect the latching circuit in the Dimmer Switch. IF the chattering does not go away, I'd .......well write back and tell us what happened.

The BLUE high beam indicator puzzles me a bit. Look at the diagram. At the very bottom of the jpg you see the legend HIGH BEAM INDICATOR. So, you can see, that blue indicator light should not be on unless the high beams have been successfully. That RW wire is tied only to the high beam side of the Dimmer Relay.

Are you saying the Blue high beam indiactor is on ALL the time? Even if your not playing with the Dimmer Switch?????? Did you change the Dimmer Relay with another dimmer relay? I mean that blue light should only be on if the dimmer relay is pulled in by the latching circuit inside the switch. Seems to me there is a gnd on that white wire to the dimmer relay all the time for some reason or other.

I'll cover my arse with the following......the headlight switch puts a gnd on the headlight relay to turn the headlights on. The part I leave out, is turning the switch to On also sends power from the HEAD fuse in the engine compartment to a circuit in the headlight switch and that circuit controls the UP/DOWN function of the headlight assy's. That circuit does not actually turn lights on/off but controls the up/down of the headlight assys. Has nothing to do with the Dimmer Switch/lever. So I'm saying that circuit isn't causing the problem imho.

One jpg attached shows the location of the DIMMER relay. The other shows what I described in the paragraph above ....more or less.

More I think about it, this is a Dimmer Relay/Latching Circuit problem. Compare the wire colors of the chattering relay with the colors shown in the diagram in diagram in my post above this one. Up in the far right hand corner is the dimmer plug and it's colors i.e. R/W, R/G, R/G, R/B, *, W.

Gotta be the latching ciruit outputting a gnd on/off/on/off etc all the time. White wire.

Make sure the high beams on both headlights are not burned out. I had that happen and it drove me nuts until I checked the headlights.

it doesn't seem to make any difference whether the headlight and dimmer relays are installed or not.
the blue high beam indicator still remains illuminated and the headlights still work. Are the headlights usually supposed to work at all when both relays are removed?

my cluster switch melted and caused everything to stop working so i took it out and connected
the headlight wire to the 12v wire to see if things were any different and nothing changed.

so we've established that the cluster switch and relays arent the problem. whats the next step to take?

Power to the headlights themselves passes thru the dimmer and headlight relays. They cannot turn on with stock RX wiring and the relays missing.

I suggest you removed the wrong relays??????? See the free online wiring diagrams for the wire colors in each of those two relay bases so you can confirm you pulled the right relays.

The relays i removed have the same number of pins as those shown. Are the relays square or round shaped?

I have a '90 Vert. The high beams do not work. I do not hear the buzzing sound you guys are talking about. I do not get the blue highbeam indicator light. My turn signal works and when the headlights are down, the FTP works. Sounds like you guys are talking about the S4 fix, I saw on here that S5 is a little more complicated. I appreciate any help ;)

Look at the COLOR or the wires in the relay base and compare them with the jpg I attached of both relay bases. IF they are not the same colors, you have the wrong relays.

If the high beam indiactor is lit up (Blue thing) then that's a puzzlement. Because the wire that lights up the high beam INDICATOR is AFTER the relays, and the same power that lights up the INDICATOR, is the same wire that feeds the HIGH beam filiment in the headlight bulb. Seee what I mean????? say yes, please.

If the high beam INDICATOR lights up, then the high beam filiments in the bulbs should have lit up also. I'd suspect bad high beam filiments in that case.

You need to replace the CPU for the electrical system. Its located on the drivers side kick panel. This is common on S5 verts. Mazdatrix sells the CPU board that you can just replace, it's not too expensive and from what I noticed it is even a bit redesigned from the original mazda board and looks much better.

http://mazdatrix.com/86-92Electrical-Chassis.htm (its the "HORN CPU" for 89-92 w/ airbag, as I am sure your vert has airbag)

Here's a series five headlight wiring diagram. Ain't no way the INDICATOR will light up without the high beams filiment lighting up.

So the only explanation I have for series five high beams being fixed by replacing part of the CPU is.....................the wiring diagrams are crooked and not right.

If the car is wired to the attached series five wiring diagram, then the INDICATOR cannot light up and not have the high beam filiment light up the headlights (unless the high beam filiment is kaput). Just cannot happen.

So I guess the wiring diagram for series five is wrong. At least the headlight diagram.

I'm stubborn. Yes.

Hailers,

I remember I was reading alot of threads on this when my s5 vert high beams wouldn't work. The regular 89-92 FSM wiring diagram doesn't list the circuit running off the CPU. Another user had a thread if you search on here where he had the actual 1990 or 1991 FSM that specifically listed the diagram for the WITH AIRBAG vert. Only on the s5 Vert with airbag was the high beam circuit shown to run off the CPU. As far as the hatch s5, I don't believe this is the case.

So yes, the regular diagrams do not apply to s5 vert with airbags as far as I can remember when it comes to the headlight circuit as it is missing the CPU part. If you can dig a FSM wiring diagram specifically for it, you will see what I am talking about and that the high beam does in fact run through the CPU.

Common symptom its the CPU, high beams don't work, with the headlights down, pull the highbeam switch, FTP works. Again though, this also assumes your high beam filaments are working. Another thing, the stock alarm system seemed to not work on my vert along with the headlights, but this could of just been more resistors burning out on the board, a new one also fixed this.

Awesome guys, I really appreciate this! I have been reading alot on my idle problem and have so much info swimming through my head, something as simple as highbeams just about threw me over the edge.

Hailers, I have read alot on the numerous problem solving techniques, and like I said, alot of it is running together and not making sense to me. It was read one thing, find another problem I have, read about it, find another and so on. So if its cool, going to research again tomorrow, and want to know if its cool to PM you instead of starting ANOTHER Idle problem thread ;) Thanks in advance!

I never look at PM's...ever. Don't waste time doing a pm. Nothing personal. I just DON'T look at pm's by anybody..ever. Never ever.

This helps some people. It's from the TEAM FC3S forum. ... http://www.teamfc3s.org/info/articles/idle.html

Usually a air leak or a *vacuum* hose going where it should not go. Like the primary air bleed air hose going to the lowest nipple on the back of the upper intake manifold.

Or the grommets on the bottom of the fuel injectors leaking air because the wrong or OLD grommets were used. Spraying fuel injector fluid under the intake manifold usually ID's this problem if the idle is low enough (500-800 rpm or so).

Using a non turbo boost sensor with a turbo ECU causes crummy idle problems....most times imho.

On a series four...cranking the variable resistor clockwise to its internal stop adds more IDLE fuel and makes for a better idle most times.

Hard to screw up the three nipples on the front of the throttle body. The all three line up pretty straight fwd.

Ilde problems are a bit of a guessing game online. I never mention sparkplugs/wires because I always assume these were checked out/changed out. Usually not the problem imho. Waste of dough most times (just an opinion/predjudice and nothing more or less). If I changed spark plugs I'd do only the lead plugs. Waste of money changing trails for a idle problem.

Cool deal, not gonna jack this dudes headlight thread for this but I appreciate it ;)
Thanks for the link!

I bet this is it.

Here is all you need to know to solve this problem. Info on the replacement board and my 'permanent solution'.

https://www.rx7club.com/showthread.p...92#post9214292

So to clear up some issues here: I, too have been dealing with this problem. I disconnected my battery for awhile to store the car, and now that i've pulled it back out the headlights no longer were working.

This thread has definately helped me out, and thanks, especially to HAILERS.

Now to clarify some issues.... this is with a bone stock (non-modified) S5 wiring. This definately is a problem with the latching circuit.

For me, when I turned the selector switch to ON (full exterior lights), the headlights would extract/retract, all exterior lights would work (including signals) EXCEPT the headlights and/or highbeams.

As per post #5, I bypass-grounded the white wire, and voila! my headlights work again. Here's the kicker... my headlights no longer retract/extract.

Either way, for the time being, working lights is good enough, but as for those who have followed the thread... All of my conditions were the exact same as the initial poster : gorge, with the exception that I started with my headlights up.

To defend gorge, upon reading this thread, I tried to hold my highbeam selection switch, and what he says is true... so long as I held that switch up (towards read of car) my high beams would stay on.

For those who wish to see this themselves (I even suggest that you try it HAILERS), if you unplug the wire harness (cluster) that runs to the light control (see attached picture - the one circled) and hold your high beam selection switch, you'll see your headlights turn on as well as the in-dash indicator light.

Note: as per the FSM that I used, the location of the relays were reversed (in my case on a 91 NA coupe) see attached picture.

Just replaced the CPU on my 91 Vert to correct the no high beams problem as described by darthrotary in post 11, above. The explanations by jjcobm and HAILERS in 13, 14, and 15 are excellent. The dimmer switch (only) is mounted on the steering column (item 1 in attachment). The latching circuit for high beams is in the CPU as they describe, not in the cluster switch as indicated on the attached diagram from my 1991 FSM. When the headlights are off, the dimmer switch grounds the headlight relay, so FTP uses the low beam filaments. When headlights are on, the dimmer switch activates the latching circuit which grounds the dimmer relay which sends power to the high beam filaments. Thanks jjcobm and HAILERS.