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Discussion Starter #1 (Edited)
So there, I said it. Going to drop my pride and admit it. I got into a rush and hooked up the car battery backwards.

Im doing an engine install, and needed to drain the fuel from the lines, so I grabbed my trusty Optima red top, set her o n the frame (like the battery normally sits in my car) and proceed to hook up the battery in reverse polarity. 5 seconds later I know something is up when the alternator starts smoking. I quickly toss the cables off and proceed to scream "WHAT IS WRONG WITH YOU!!!!!"

Anyhow, I immediately inspect the fuses, none are blown. Check the fuses up front under the clam, nothing out of the ordinary. I hook up the battery correctly and all the lights, blinkers, alarm, immobilizer, everything seems to work fine. I go to start the car and its kind of cracking and popping and making weird noises (I have the straight pipe and muffler off) so I chalk it up to not having a good enough connection on the terminals. I snug the cables onto the battery terminals and go to re-start. After my second attempt she starts right up.

For not having the exhaust connected nor the O2 sensors she seemed to run ok. Just had a high idle to start with, followed by a fluctuating idle, then a steady idle. I blipped the throttle a few times and she seemed responsive as well. At this time I deemed it ok to pull the fuel pump fuse and let the pressure die out. After doing so she ran another 10 seconds just fine and died.

My question is, does Lotus protect against stupidity? Is there an inline fuse somewhere in case of something like this happening? I have no blown fuses, everything in the dash works, alarm/immobilizer works, and the car starts and seems like it idles just fine (as far as I can tell with muffler off and sensors unplugged).

Can anyone chime in for the following question: If the battery is hooked up backwards for say a total of 10 seconds, is it possible to get away scott free without anything happening?

Thanks guys & never again will I make that move, especially since Im replacing my whole engine with a whole new longblock!
 

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Carbon Fiber
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Hooking the wrong terminals up on the car is pretty much like not hooking it up at all. Now try n charge the battery with the chargers cables swaped and hello 4th of July!
 

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Discussion Starter #6
Thanks guys. Im curious, is there some kind of preventive measures built in just in case something like this happens?
 

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Thanks guys. Im curious, is there some kind of preventive measures built in just in case something like this happens?
They must have done something. The original owner of my car (MY02) did the same and fried the ECU and the dash... (replaced before I took ownership).

Yes. It's the main fuse that will save you
The main fuse won't do anything except protect against over current (short). To protect from reverse polarity you need a diode (which the newer cars may have).
 

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well did the same thing last night

it was for a split second however my dash is acting crazy ie the needles jump around when driving and can not go over 6000rpm ie it is in limp mode even after warming up!

any input suggestions etc would be welcome!
 

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The main fuse won't do anything except protect against over current (short). To protect from reverse polarity you need a diode (which the newer cars may have).

Yup some ECUs have diodes in them.
(Sort of like a scene from Pinnochio but with electrons instead of donkeys.)
 

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Your car is now a magnet. Are tools sticking to the clam? Cut your losses while you can!
 

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Look for burned wiring as well...

I once put out a fire in a Porsche RS America at the local auto parts store. The kid from the store and the owner hooked up the battery backwards (they were pounding the small clamp onto the larger post!). The wiring in the engine caught fire, melted through the AC line insulation, and melted the engine fan shroud!

I had my fire extinguisher in the Lotus, so I put the fire out, since the extinguisher in the store was empty.

And no it didn't run after that...

Good luck with your car lt0302!
 

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that is what I am doing right now after

Have you tried disconnecting the battery for an ecu reset?
checking all the wires and functions. Everything works ie ac, gas guage, temp gauge, engine starts right up, lights, dimmer, tell tell, turn signals, cooling fans, checked the wire harness going into the ECU no signs of burns......granted it was only for a split second.....as soon as it sparked I knew something was wrong.......now I will live the battery disconnected till tomorrow and get back with an update!
 

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Good news

After an overnight battery disconnect all is back to normal!....:D dodged a bullet there!
 
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