I hooked the battery up backwards, Oh S##T!
 

I'm putting in a Vintage Air kit and had the battery out for a long while. I accidentally hooked the battery leads up backwards when putting it back in.
After a shot time when I realized what I did, I then hooked it up correctly then checked all fuses that I know about and they were all good.
Now when I turn the key to the on position, all gages come as like normal, the ECU light turns on as normal and I hear the fuel pump running , but only for about 3 seconds. Then it seems to all go dead. Obviously I turn the switch to ignition and nothing happens. If I turn it back off and wait then turn to on it does the same thing.
I feel like an idiot.
Does anyone have any advise?

Re: I hooked the battery up backwards, Oh S##T!
 

Will ot start? The fuel pump os supposed to shut off after a few seconds if the engine isnt running.

Re: I hooked the battery up backwards, Oh S##T!
 

No, It won't even try to start. It seems like the computer shuts it down after the three seconds. It all goes dark.

Re: I hooked the battery up backwards, Oh S##T!
 

It's not a ls swap problem, sounds like a starter signal wire problem. No one ever wires the factory starter relay in, so I would check to see of your getting 12v to the starter signal wire and back track from there.

Re: I hooked the battery up backwards, Oh S##T!
 

Thanks,
Yes your correct It's definitely not an "LS swap problem". Everything has worked fine for a long while now with the LS swap. The problem only happened after I removed the battery to route the hoses for my A/C. Then I put the battery back in and accidentally connecting the positive cable to negative on the battery and the negative cable to positive in there battery.

I'll definitely start looking ate relays. After I turn the key on it all acts correct for 3 seconds then it seems like the computer is telling a relay to kill power. Thats when all the gages and every thing else shuts down. Even the screen on my ride tech control starts to slowly fade to black.

Re: I hooked the battery up backwards, Oh S##T!
 

Check the charge on the battery.

Re: I hooked the battery up backwards, Oh S##T!
 

Theres no way the computer will shut off the gauges and your arivride controller. Hooking up a battery shouldn't kill a battery either but wouldnt hurt to check the charge. To me sounds like you have a loose connection somewhere, like a loose battery cable or connection at the starter if that is where your harness is getting its power from. Or maybe the junction block on the fender.

Re: I hooked the battery up backwards, Oh S##T!
 

Check ground wires if you haven't.

Re: I hooked the battery up backwards, Oh S##T!
 

Thanks guys,
I think your all leading me in the right direction.
A little more info; After it goes through its normal start up of about 3 seconds, then things seem to die over a second or so. The LED display on my Ride Tech controller slowly goes black. That seems to me like it loses voltage.
Ive read on some other forums that it could be a fusible link or it could be a voltage regulator. Ive also read that the voltage regulator is probably inside the alternator.
Can any one tell me the best way to check for all the above? I have a multi meter.

Thanks a Lot

Re: I hooked the battery up backwards, Oh S##T!
 

Put the multimeter across the battery. 12.4v or higher? Turn the key on. What does it read?

Re: I hooked the battery up backwards, Oh S##T!
 

Ignition switch heats up and overloads maybe? What year vehicle??

Re: I hooked the battery up backwards, Oh S##T!
 

Its a 1972 C10

Re: I hooked the battery up backwards, Oh S##T!
 

I’ve had my 65 ignition switch act very weird before and replaced it, issues fixed. Dash wierdness and shutting off etc. just a suggestion.

Re: I hooked the battery up backwards, Oh S##T!
 

* *Thank goodness I found the problems,
first problem is that I'm an idiot.
Second problem is the 60 amp fuse on the firewall. Which is a hell of a lot cheaper than a new computer to replace.
I checked this fuse immediately after the problem first happened with my meter on the two little exposed leads on the top of the fuse. It showed continuity. It wasn't until I pulled it out and looked at it that I saw it was not good. I guess it had a tiny bit of connection left the first time I checked it.*
**The engine starts up and runs fine now.
* Thanks a lot guys for pointing me in the right direction. I hope you all at least got a chuckle out of my stupidity*

Re: I hooked the battery up backwards, Oh S##T!
 

glad to hear it was that simple....

Re: I hooked the battery up backwards, Oh S##T!
 

Awesome!!

Re: I hooked the battery up backwards, Oh S##T!
 

No chuckle here , Its the most simplest things that will drive you crazy . Some times you have to ask questions to get your mind working in the right direction .