Toyota verso, battery went flat,crossed terminals during jump starting,now efi relay is noisy, all fuses checked in the engine compartment, engine cant start.

 

Hmmm. A head scratcher.

If the EFI relay is bad, you will be able to crank it but it won't fire and start (no power to the ECU). Since your relay is "noisy," I would start by checking that. That is why you have a multimeter.

Crossing battery terminals, of course, can damage lots of stuff. So if the EFI relay is good, you need to describe your problem. Will it fire, chuff along for a bit, then quit? Will it fire, but keep going? Will it crank, but not fire at all? Will it not even crank, just relays clicking? Or when you turn the key, do you get silence? All of these things are "engine can't start," but they all point to different causes.

 

Year and engine would help. Crossing the jumper cables on a 22re in the cases I have seen blows the 80 Amp fuse. How to Replace 80 Amp fuse >>> >>>> https://www.yotatech.com/forums/f199...l#post51747852 >>>