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CB125T, EX250 commuter, Ninja 250 racebike, CBR250R(MC19), VF500F, CBR600RR, VFR750F
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Pull out multimeter and test voltages along flow of electricity from battery to starter. Where power disappears shows fault is between that spot and previous one that did have power.
 

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CB125T, EX250 commuter, Ninja 250 racebike, CBR250R(MC19), VF500F, CBR600RR, VFR750F
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no power, so have to do continuity only. I would have to disconnect the whole harness to test it. or make multiple cuts into every wire.
No power at battery? Those bastards sold you bunk battery!!! Should return battery and get one that has power. Please post photo of battery.

Don't have to cut wires to measure. Back-probe connectors along path between battery to starter to measure power. Or unplug connector and probe terminal inside.



This is 5-minute fix with multimeter (or less in many cases).
 

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CB125T, EX250 commuter, Ninja 250 racebike, CBR250R(MC19), VF500F, CBR600RR, VFR750F
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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.
 

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CB125T, EX250 commuter, Ninja 250 racebike, CBR250R(MC19), VF500F, CBR600RR, VFR750F
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840 Posts
Yup, problem is those other wires that triggers soleniod has to have power from B-terminal through 20a main fuse (in this bike). So after confirming voltage at B-terminal, measure input and output power at main-fuse (which is in fusebox on this bike). Lack of power on fuse-output will indicate it's blown, don't even have to pull fuse to measure it.




However...in this case, when battery/starter-cables are connected backwards, no power leaves solenoid to power 20a main fuse, fusebox, ignition-switch or start-button. I'm assuming when he says "no power", turning key ON doesn't light up dash, doesn't turn ON headlight, doesn't power start-button or anything on bike at all, no horn either. Completely dead. We've gone from bad (sizzling) to worse, completely dead.

I was outside in TX, where it is always windy, no way to smell it, just hearing the sizzle. but, it would still turnover, until finally gave out with a sizzle and popping sound.
I did replace the starter solenoid which is where the sound was located, but still won't start.
no power, so have to do continuity only. I would have to disconnect the whole harness to test it. or make multiple cuts into every wire.
 
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