Vermillion

My RX-7 had been sitting for about a month, and when I went out to start it, it didn't have enough juice in the battery to turn the engine. No problem, it was an old battery anyway.



So I got a new battery, and I just put it in. Now almost nothing works. If I turn the headlights on, they don't come on, but the marker lights do (nice and bright). NOTHING else works - no interior or dash lights, no stereo, no headlights, and no starter. Just the front and rear marker lights. I'm pretty sure the battery has plenty of huice, it's just not going anywhere.



I'm going to go out now and check the fuses, but what are the odds that I managed to blow the fuses that control everything but the marker lights? Can anyone think of anything else I can check to find a possible culprit? There's a mass of wires under the dash, but I have no idea what any of them are for. :P



Any help would be much appreciated!

Vermillion

Grrr, I've definitely got a short somewhere. I found a 7.5 amp fuse that was blown, so I went to replace it, and the new one blew the instant the contacts touched.



I guess it's time for me to go look at a giant knot of wires with a serious look on my face, in an effort to convince the wires somehow that I know what I'm doing.

Rob x-7

Disconnect the negative battery cable from the battery and take a test light and connect the one end to the battery cable and the other to the negative terminal of the battery, your test light should be lit at that time.



Start pulling the fuses in one at a time, being sure to close the door and turn everything off otherwise they will come up as a open circuit. When your test light turns off, thats where the short is.



I think the 7.5 amp fuse is for the radio though, you do any radio work lately?

Fastrotaries

make sure that the fuse is of the proper rating. my first car had one with a rating that was too low and would blow frequently. turns out it should have been a 15. big difference.

Vermillion

I'm pretty sure it's not the fuse's fault - I hadn't messed with any fuse the entire 5 years I've owned the car, and now all the sudden any fuse that touched the contacts instantly blows.



I had finally managed to find a buyer for this car - he's supposed to come pick it up on Friday. I swear to god, if this deal falls through because I can't figure out the electrical problem, I'm going to call a junkyard and have them tow it away.

hayas-fc

go onto amazon.com, look at the books they have for the rx-7, buy the one that says Haynes Repair Manual, its very good and only about $17, it has all the wiring schematics you will need, i would send you the pages through the internet, but i dont have a scanner, good luck

rotarychainsaw

Make sure you put your battery in right. I put mine in backwards (D'OH!!!) blew my main fuse the instant it touched. I forget how to tell which wire goes to which terminal though.

Vermillion

I'm correct in thinking that the battery connector toward the back of the car, with the black rubber cover over it, is the negative terminal, correct? Because I do think that the symptoms seem similar to if I had it in backwards, but from everything I can tell, I don't.



My main fuse is the one blowing out now, just like you said, rotarychainsaw. Hell, maybe I'll turn the battery around and try it that way, even though it looks wrong. First I guess I'll have to go find someplace that sells 80A fuses. :P

Vermillion

Holy crap, I think I had the damn battery in backwards. I would now like to submit my nomination for dumbass of the year. I'm just one new fuse away from testing this out, but the lights work now.



Who puts a black rubber cover over the positive battery terminal?

FCmaniac

ha, holy ****... well, its good you figured that out... would be a shame to send another 7 to the junkyard because it can't be fixed.