junito1

OK. I was driving the other night, when all of sudden the back light to my intire dash when out.
I talking about gauge cluster back light.
Radio,a/c, etc backlights went out.

A few days later i realized my tail lights didnt work neither. Brake lights do though.

ANyways. I sure it has to be something behind the dash.

SO im looking for a clean legible wiring diagram.

Aaron Cake

iTrader: (1)

You'll find the wiring diagrams in the back of your Haynes manual, or in the Factory Service Manual which you can download for free from the FAQ.

However you don't even need to check those manuals because according to the FAQ, this is a common problem with the headlight switch/harness. Check the FAQ for details.

pfsantos

iTrader: (1)

Aaron - are you alluding to the famous headlight switch problem?

junito1

WHen i search the faq it never comes up w/ any results to any terms

Also.

The same day this all happened i found a black wire approx. 1 ft in length sitting on my diver side floor mat. I looked around to see when the hell it came from w/ no results.

It was a spliced wire. Definately something aftermarket.

BrettLinton7

iTrader: (33)

The same thing happend to me and it was just a fuse... check all those before you buy something expensive like a new headlight switch :-)

Craiger

iTrader: (1)

^+1

I was a dumb *** and when this happened to me I did the switch rebuild and nothing changed. Then I discovered that it was the fuse. I could have saved a **** load of work!!!

Here is the writeup on the wiper switch fix. https://www.rx7club.com/2nd-gen-archive-72/write-up-rebuilding-your-headlight-switch-383384/ It's a little trickey.

junito1

Interior fuse box fuse?
2 days ago I checkes all fuses. Engine bay and the interior fuse box.
All fuses were good.

I tried switching the head light switch. But I had the same results.
Headlights work, Nothing illuminates in the interior. Tail lights dont work(brakes light do), My hazzards work but my turn signals dont.

It should be easy to fix now. SInce i got mad and took the whole dashboard OUT!.
All wires and connectors are all in the open for fixing.


All i need is for some of you to guide me through it.
Oh and the harness that connects to the headlight switch did not look burnt out......

junito1

OMG!!!!!! nearly 300 bucks for a switch!!!!!!

Craiger

iTrader: (1)

Since your fuses are good it's probably the switch. No need to rewire everything so far.

Just a crazy idea, but did you pull the fuse out and look at it? When mine went it actually didn't blow the fuse, it melted it (the fuse didn't look bad when it was still in the block). Because of this I had to do a little rewireing. Might be worth a check before you dis-assemble the switch.

HAILERS

You take the elect plug off the switch.

You find the White/Green wire in the plug.

You find the Red/Green wire. It's next to the W/G.

You get a piece of wire, bare at each end. Put one end in the W/G and the other in the R/G.

The lights should have lit up IF all the OTHER plugs are attached to where they go.

The tail light will NOT have come on. You jumper the W/G to the Red/Black to get them to work.

So? What happened?

What year car is this? A 86 or a 91?

junito1

My car is an 88

junito1

Ok guys. How do i Know if the back of the light switch is burnt? Does anyone have any pictures?

I did notice the Big blue light/turn signal switch harness plug had more of a green tone instead of the nice bue like the other behind the dash.

Craiger

iTrader: (1)

Post a pic of what you have and someone will be able to let you know what they thing is going on.

HAILERS

Get someone to help you and do the above.

Icemark

You read the FAQ for FC and didn't find:

junito1

Yes, but how does that help me know if they are burnt. EVerything was intact and looked in good condition.

Hailer. I tried this and could not get the back lights to come on.
I'm pretty sure i did it right.

But, I will try again. just to make sure.

Icemark

Did you unplug the harness at the back of the switch?

Are there any dis-colored/burnt looking wire pins in the plastic. The plastic turns from opaque white to brown and black when it is burnt, but only around the pin/wires that are having the issue.

particularly the white/green, the red/green and the red/black

If the switch and plug do not look burnt, then your switch may have internally failed if you have power on the white/green, but none on the red/black when the parking lights are on.

But that is pretty rare. Maybe 1 in every 1000 do that.

2slow4stock

iTrader: (18)

Maybe the grounds came loose. Who knows, if it wasn't fuse why not check grounds?

Icemark

Because you are talking about 8 different grounds in 8 different locations all failing.

Gee, what do you think the odds of 8 different grounds all failing, so that they guy has no parking lights and dash lights?

Maybe you would loose one ground and the front bumper lights stop working, but this guy has all the lights out, except the ones that are triggered by a ground (the headlights).

Please don't post if you don't know.

2slow4stock

iTrader: (18)

Well... may bad... It never hurts to check. Its the little things that make big things happen. (>_<)

HAILERS

If you jumpered the wires as described and the lights did not come on, then either the White/Green wire has no power on it, or the light switch harness that electrical plug is attached to, is no good.

The White/Green is the power wire, so if it isn't getting fused power, things ain't a gonna work. You need to put a meter on that White/Green wire to see if it has batt power or find out some other way if it has power.

The harness that connects to the light switch is not very long. Maybe two feet long. It could be bad.

HAILERS

https://www.rx7club.com/attachment.p...6&d=1204850214

Tell you what. Since that light switch harness is but two feet long, you could find the other end of it under the dash. Then do the Jumper job I described above.

What this does is eliminate that short lighting harness altogether. IF power is on that White/Green wire, and you jumper it to the wires I described above, then the tail light etc should come on. You jumper the plug the light switch harness is plugged it to, not the light switch harness side of the plug.

Just a common piece of electrical wire with both ends stripped. One end of that wire in the White/Green wires socket and the other end of that same wire stuck into the Red/Black wire. Lights should come on.

Like I said, you do it this way to eliminate the light switch harness. The plug that the light switch harness attaches to at the other end, is a 17 socket/pin plug. The White/Green wire should be on the top row, 4th wire over from the end.

Make sure the BTN fuse is good in the engine bay fuse box. It's on the very outboard end. Probably is good.

It's the ILLUM fuse that gets fed by the BTN fuse that supplies power to the White/Green power wire at the light switch plug. See fuse box cover.

It really does sound like the short harness connected to the light switch is kaput. But just for grins, go to the other end of that short harness and do the jumper job I described above. Success is just a few minutes away.

HAILERS

The actual harness that is connected to the headlight switch is shown on this site: http://www.mazdatrix.com/86-92Electrical-Chassis.htm

Just find that BLUE plug on the other end of the light harness, and jumper the plug IT is attached to.

In a plug with burnt wires, you'll probably see black soot on and near the pin in the plug that is bad. And if really bad, you'll see the plastic near the pin melted. You can't miss seeing it. It sounds like your don't have that problem, at least not at the headlight switch side of the plug. Maybe at the OTHER end of the plug???? The BLUE plug end????

junito1

I have a tester.
SO start by testing the W/G for power. Then turn the light switch on and test the r/b?

HAILERS

See the picture of the light harness I attached to my last post? Find the Blue plug on your car and pull it off. Then find the white/green wire in the plug it was attached to. With your *tester* see if that white/green has batt power or not. IF it does, good. If it does not, then your problem lies b/t that white/green wire and the ILLUM fuse or b/t the ILLUM fuse and the BTN fuse in the engine bay.

IF you have power of the white/green wire, then that's good and you just need to make a jumper wire to jumper b/t that white/green and the Red/Black wire in that plug. Lights should come on.

The light switch isn't in the picture. You don't need to turn it on/off because the harness isn't connected to it.

What your trying to do is determine if that short harness is your problem or not. You can just take it out and lay it on the kitchen table if you want. Your jumpering the plug on the car the Blue connector was connected to. Jumpering the white/green to the red/black should make the lights come on. Key does not have to be in the ignition. If the lights do come on, then the problem lies in that short harness or the light switch.

Earlier, when the short harness was disconnected from the light switch, and you jumpered the white/green to the red/black, and said the lights did not come on. The only obvious reason for them to not come on, is if the white/green does not have power or the short harness has a bad connection in it. Can't be the switch because it's out of the picture.

You can look at that wiring schematic and find the WG wire. You can see how it goes to a connector called X-17 in the schematic and is fed from a fuse thats got 15X next to it (ILLUM fuse) and then goes to a 60A fuse (the BTN fuse in the engine bay).

When you jumper the white/green (WG) to the RB, you just bypassing the possibly junk parts inbetween. Your trying to find out which part is the bad actor without having to buy a new/used switch or a new/used short Light harness.

If there's power on the white/green and you jumper it to the red/black, and the rear light don't come on...........well for right now that seems very unlikely.