Just pull the fuse ... and see what quits working ....
Ha Ha Ha!! I love it. This method does work! But I'd rather use a schematic.
This is sort of in the same vein:
I once had to service my Jeep because it kept blowing ECM(brain) fuses. On the third trip, as the service adviser was giving me my keys, he told me they didn't know why it was doing it and couldn't fix it. I told him I could find the problem in minutes without a test meter or ANY tools. Surprised that a common schmutz like me could do this without "factory" service training or expensive equipment, he asked me "How?", (He was obviously looking for a "free" undocumented, money-making service tip, so I gave it to him)
I offered to wrap the ECM fuse in aluminum foil to demonstrate where the problem was originating (I told him to simply look for the smoke, but keep an extinguisher handy
He took it back in the shop immediately and the problem was miraculously repaired in minutes (unfortunately without my rather rudimentary, but very effective test procedure
) It was the ECM itself, just as I thought and am still on that same ECM today 10 years later. I love dealers (sarcasm) and NEVER, EVER, give any of them the benefit of the doubt (Kaw dealers included).