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Help needed car wont start

I drive a Che Aveo 08, I was tryin to take out the battery while the engine was running, whilst doing (loosening the positive terminal)that my spanner touched the edge of the computer box sparks few…and the engine cut off…now it wont start , everything comes on but when i try to start…the engine doesnt seems to catch the spark.

Did you check your fuse box for blown fuses? The fuses are designed so that if too much power flows through, they will pop and will not allow the function to work until replacement. Chances are when you touched the computer, the fuses did their job by not allowing any more power to flow through and possibly melt wires and/or start a fire somewhere. That is where I would start. It all fuses appear to be fine, I would get more professional help from a dealer, or a small independent garage to do more diagnostic testing. Does the check engine light shut off after a few seconds of the ignition key being turned to the “on” position? If not, it could be a good start for a mechanic.

Never remove a battery while the engine is running for starters. It can kill your alternator and possible the vehicle computer. If you are very, very lucky it will be a blown fuse. If not you may have fried your computer. I would see an independent mechanic to try and sort this problem out.

Since the short was a direct one from the battery post to ground you may find there are no bad fuses since the high current from the short went through the wrench and the module frame ground and not the main wiring. Check the small ground wires around the engine and chassis for signs of burning.

Even though the wrench touched ground you may have damaged the control module that the wrench touched due to electrical spikes. I’m not sure if that is the ECU or it may be a PCM module. I wouldn’t be surprised if you end up having to replace it. Consider this a good lesson. You should never work on the battery while the engine is running in todays’ cars. Disconnecting it could cause electrical spikes from the alternator to damage electronics in the car. The battery helps filter these spikes out of the electrical system. It is also best to disconnect the negative side of the battery first when working on it. That way if you do touch ground while working on the positive battery post no short can take place since the negative connection is removed already. Shorting the negative side of the battery to ground does nothing since it is already tied to ground.