Spent 6 hours chasing a no start on a 2007 Corolla only to find a blown 15 amp fuse labeled IGN2
Customer had it towed in on a Wednesday morning with no crank, and I went through grounds, relays, the starter, and even swapped the ECM from a junkyard unit before I thought to check the under hood fuse box. Pulled a 15 amp fuse labeled IGN2 that looked fine from the top, but the test light said it was dead, and 30 seconds with a new fuse had it running. How many of you have a rule for checking fuses first before you start throwing parts at it?
Man, been there. Pull the fuse and look at it good, or just hit it with a test light on both sides. That little gap in the wire can hide under the plastic and look fine from up top. First thing I do now is yank every fuse in the box and check them with a meter. Takes five minutes and saves a whole day of chasing your tail.