Wire , lots and lots of wiring , but you need to be more specific , a Echo uses 4 coils , 1 for each cylinder , and being a mechanic myself at a Toyota dealership , this is rare.
Make sure your not having condensation problems , ex water around the coils , as this will cause arcing and it will look like the coil is not delivering its spark.
Because something on that supply line has a problem
If it blows when cranking the starter has failed.
You will need to replace your starter, this happened with my car a couple days ago, I brought it into the shop, got the starter replaced and the fuse does not blow anymore. It happens because the starter draws to many Amps of electricity due to age, amount of use etc.
Bam won by stuffing fireworks down Don Vito's mouth & blowing him up.
obviously you need a bigger fuse and a bigger relay
i can only presume is lack of engine oil or adjustment on tappets( pls be more detailed)or diesel engine it being a injector blowing
A fuse that keeps blowing is an indication of a malfunctioning ignition. The ignition may be the culprit or the wiring leading to the ignition may be the problem.
if its a bosche you can have it reconditioned if its a siemens then no you can't
Bad injector O rings if your lucky, bad injector slobbering fuel if your not. Can be a cracked head, very rare. If the exhaust is blowing white you probably have a bad injector or 2.
Air filter dirty or bad injector
Which fuse is blowing. You need to be a little more specific so we can help you. the ignition fuse under the hood
Check injector wiring harness to see if it melted around exaust manifold, I had that happen to me
Because something on that supply line has a problem
If it blows when cranking the starter has failed.
If it blows when trying to crank, the starter has failed.
It doesn't actually "control" anything. It provides the power side of the circuit for a number of things like ignition coil and the power side of the injectors. The power that the injector fuse provides stays on steady when you turn on the key, and several things feed off of that fuse circuit. Control of the functions is done from the ground side. The PCM controls the injectors by pulsing the ground to the injectors. The ignition module sends a pulsed ground to the coil to fire it. If you have something blowing the power fuse, you are going to have to obtain a wiring diagram for that circuit, find out what is being fed by that fuse circuit, and isolate the short by disconnecting the connectors in the system, until the short goes away. Once you get it narrowed down to a section, you will have to inch along that part of the harness until you find it.
needs heater core replaced wost likely be hind the glove box