mjm4jc

I got the instrument cluster out, but can't seem to locate the over-rev buzzer. I'm suspecting that this is the cause for my lack of lights, etc. If the buzzer is fried, can I just bypass it in order to get everything else working?

dennisracing3

possibly or check your tail lights? Use to happen in one of my previous cars with fuses.

mjm4jc

This is related to a previous post of mine, whereby I lost all lights, interior and exterior, after my throttle got stuck momentarily. I already replaced the alternator to eliminate that as part of the problem. Now that I still don't have lights, I'm suspecting that the over-rev buzzer is fried. According to the schematics, the over-rev circuit is linked to many other circuits. Just trying to get her back on the road.

Brigdh

iTrader: (9)

maybe this will help?
http://www.jimrothe.com/mazda/overrev.html

mjm4jc

Yeah, I already read this. It really isn't any help as far as identifying the buzzer. I didn't have to take the steering wheel off to get the instrument cluster out. If you take out the steering column bolts, you can drop the steering wheel about an inch or so, which is just enough to get the cluster out and passed the wheel. Anyway, I did not see anything in there that looks like an over-rev buzzer. I know I have one, because it buzzed all the time :-)

Mr_Miles

iTrader: (1)

!! I've been looking for that. Thank you.

mjm4jc

I think I have bigger issues than the over-rev buzzer. When I turn the key on, I have nothing----zero. What I found odd in all of this is that on the headlamp fusible links, the middle one will burn up the fuse immediately. Remember, this is an SE, so I have two on the top for ECU and FI and 3 on the bottom for headlamps. The other thing is that I was looking at the main relay and it seems that I should have two power wires going to it. Wires 1 & 2 should have power and three is ground. Is that correct? I remember some time ago probing the connector for the main relays and two wires had power. I would appreciate any help. I looked at the wiring diagrams, but I'm not proficient in reading the schematics.

mjm4jc

Here is the original thread that lead to the issues I'm having now:

https://www.rx7club.com/1st-generation-specific-1979-1985-18/lights-out-burning-smell-927280/

74RX4

iTrader: (10)

Main relays should have power to 3 wires each when ignition is on. White wire to one relay and White/blue wire to other should have 12v all the time. They are from FI and ECU fusible links that are only on the GSLSE. Black/white wires go to both relays and get 12v from ignition switch when it is on. Red/white (ECU) should get 12v (from White/blue wire) when ignition switch is on. Black/yellow (FI and Ignition) should get 12v (from White wire) when ignition is on.

The fusible links that all cars have are marked. "Retractor" protects a White/red wire that supplies main power to the headlight retractor motor relays. "Main" protects a White/red wire that supplies power to the fuse box and Ignition switch. "Head" protects a White/green wire that supplies power to the Combo switch to power the headlights only.

Main (center) link you are blowing protects the fuse box and Ignition switch.

mjm4jc

Thanks man. I'll have to take a look at the ignition switch.

BTW----What is this oscillator I see in the diagrams?

Marx-7

When i read this it reminds me of a problem i've had with my FC. Same engine so maybe this will work as well.....i hope

A few years ago i was driving the FC (bad weather) and all of a sudden it died on me. Nothing worked turning the key but strangely the only thing that did work where the headlights which pupped up (but no lights) and the danger lights.....that was all.

When i tried to identify the problem it was a heavy fuse which blew out. When we got the FC home i had the time figuring out what to do and i touched a groundcable in the neighbourhood of the battery and the headlights went down so i knew that i found my problem. The problem was a bad connection and when i cleaned that connection the problem was gone. That cable (black) is directly under the fuses in your enginebay.

I must have a picture of that somewhere and i will post it when i find it. i hope you can do something with this info.

Marc

mjm4jc

Thanks Marc. I found a problem that is definitely related to my having no power at the key. When I hook up the alternator, it blows the main link/fuse. I just bought this used S5 alt that was tested to work, but when I hook it up, I blow the main fuse. I followed the instructions on the S5 alt swap in the archives. Not sure what I have wired wrong. I'm hoping that the alt isn't bad or shorted, since I just bought it. I disconnected the alt completely and the car has power and starts and runs fine. Any suggestions?