Q: Car blows ecm run/start fuse after starting and then dies replaced fuse and repeats

asked by on June 23, 2017

So what happened is I was checking spark plugs and I accidentally touched the wrench to the positive battery terminal causing it to weld the wrench an art to it blew my 100 200 amp fuse on the battery post replaced it car ran fine and drove fine for three days then as I was driving at home it died towed it to fiance's parents house inspected all fuses to find fuse number 45 ECM Run start fuse was blown it is a 5 amp fuse replaced the fuse with another 5 amp fuse started the car and the fuse blew again after a few seconds and the car turned off again no visible damage wires upon visual inspection by myself

My car has 120000 miles.
My car has a manual transmission.

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Hi there. Typically when this issue occurs, damage will be instant - meaning if it’s going to damage the ECU, replacing the fuses would not help start the vehicle. So, at first glance, I would assume the ECU is OK. What is more likely is that you have an exposed wire somewhere that is causing the fuses to pop. Trying to diagnose these issues can be tricky sometimes, so it might be a good idea to have a professional mechanic complete an electrical problems inspection to isolate why you’re having these issues and recommend the right repairs.

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