I have a completely stock 1988 RX-7 convertible (46k miles) that I got from the original owner eight years ago. I drove the car regularly until about two months ago when I got in, turned the key, and there was nothing. No lights. No dinging. Just dead. The battery is less than a year old. Two or three time I've tried attaching a jump box. Still nothing.

 

These are my suggestions (check in the order listed):
1. Recheck your battery and clean the battery terminals. It's not unusual for a new battery to die prematurely.
2. Check the battery ground cable.
3. Check that your getting about 12V at the starter positive (+) terminal.
4. Check the fuses in the main fuse block next to the battery especially the main 80A fuse.
5. There are two wires that attached (i.e., bolted) to both sides of the 80A fuse in the main fuse block. Check that you're getting 12V at both these wires.
One (or more) of these 5 items are most probably causing your problem. Let us know what you find?

 

I suspected a fuse or something like that, but didn't know how or where to begin. Thank you, Hot Dog. I'll check out the main fuse box next to the battery, especially the 80A fuse.

 

The hope that this was a common problem and an easy fix died after shaking the cables, replacing every fuse in the main fuse block, and putting on the jump box again, all to no result, which about exhausts my electrical-problem-solving abilities. I'll try to find someone willing to take on tracking down an electrical issue on a 33-year-old Japanese car, get it trucked there, and cross my fingers that it doesn't end up costing more than the car is worth. The Mazda dealer wants a non-refundable $300 before they'll even look at it. I still don't understand how overnight it went from being a completely-reliable 2-or-3-times-a-week driver to the world's biggest paperweight.

 

http://foxed.ca/indexmobile.php?page=rx7manual


I just gave you the link to all of the full service manuals, including the entire wiring diagram. For you or whoever to reference when figuring out what’s going on with the car. Owning an old car, you really should learn some electrical and go in with a multimeter to start testing for power, continuity, etc.

Once you learn the basics, you’ll be able to almost diagnose anything. If it was me, I’d be checking for power at the battery post itself, then the terminal, power going to and out of the fuse block, ignition switch. Then check continuity for battery negative to the chassis. Then I’d refer to the manual.

Do you have power to anything? Headlights, brake lights, hazards? Did you check the fuse block under the dash on the driver side?

 

Do you have a multi-meter? If not, buy one. It'll be your best friend for this. Did you check the wires that attach to the main 80A fuse? One of them attaches the battery harness to the chassis harness. If this wire isn't connected or isn't see 12v you won't have power to a lot of things. Like hot dog said start checking to see if the things that should have 12v have 12v.

 

I'm not saying that this is your problem, but it'll give you some insight. Your battery cables are 30+ years old. Take a closer look at them and replace if necessary.
Read the article on Repair Mistakes & Blunders https://www.rockauto.com/Newsletter/...s/2-18-21.html

 

A quick follow-up: It turned out to be the battery. I never had one go out in less than a year, and go out so severely that it wouldn't even allow a jump start. Anyway, the auto parts store did a free exchange for a new one, and the RX-7 is back on the road.

 

Nice to know you found the solution. Im not sure what battery you had, but ive seen the autozone batteries fail quite frequently(during my time as a shop tech), to the point where I wouldnt install them anymore for customers.