No need to disconnect harness right away. When tracing power from battery to starter, if you measure loss of power, then back up one connector and examine it closely for why power stopped there.
In this case, battery and starter cables are just connected backwards at starter solenoid.
This is how power flows when cables are connected properly (ignore colours for different bike).
- power goes from battery to B-terminal of starter-solenoid
- then goes to fusebox
- goes across 20a main fuse
- then power to ignition-switch
- turn ignition-switch ON and it sends power to lights and arms START-button
- press START and it activates starter-solenoid which connects B-terminal to M-terminal
- M-terminal sends power to starter motor.
Here's what happens when you have battery & starter cables reversed at starter-solenoid:
- power from battery goes to M-terminal of starter-solenoid
- since there's no connection from M-terminal to anything else, power just stops, doesn't go to fusebox or reach ignition-switch, doesn't power lights when key ON, doesn't arm START-button, nada, zilch...
TO TEST AND DIAGNOSE THIS NO-POWER PROBLEM
1. Of course 1st test in any electrical issue is to test power-source:
battery. If his battery is really bullocks with ZERO volts, then he should return for good battery
2. then, follow path of power to next junction:
B-terminal of starter-solenoid
In this case, because cables were reversed, there will be ZERO VOLTS, NO POWER at B-terminal and ZERO power at fuse-box and ZERO power at ignition-switch and ZERO power to lights and ZERO power to arm start-button, and ZERO power to starter-solenoid when pushing start-button and NO CLICK and ZERO power to spin starter motor.
