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eletrical problem (ignition i think)

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by Aprilia, Dec 11, 2011.

  1. hey guys!

    so a few days i tried firing up my aprilia (rs 125) to go to work and nothing happened!
    so i switched my key off and tried again, checking that it was in neutral, kill switch yatta yatta yatta
    and yet again nothing :S there was no spark :S
    i recently changed my spark plug about a month ago, i took my battery out and charged it all night, i checked my fuses
    anyone encountered something like this before and can lead me in the right direction please ? (catching a taxi home from work sucks >.>)

    thanks in advance!

  2. Just to confirm when you say nothing happened:

    No clicks
    No crank
    No gauge lights
    No headlight.

  3. there is a click
    but no cranking
    gauge lights and headlights both work so im thinking its not the battery
  4. Yes and no :) To crank a large amount of current needs to be available. A high resistance connection to the battery can allow lights, gauges, and the starter solenoid to engage but when the high current needs to flow to the starter motor the voltage collapses.

    As you have said you had the battery out I would check the terminal connections to the battery itself. They need to be tight, if the battery has build up clean them off and reconnect the battery.

    If that fails you move on to the high current connection from the starter solenoid to the starter motor. Are they all tight good connections?

    At that point it may be getting beyond what you can do on the bike when it is still at work, depending on how understanding your boss is. ;)

    Then start looking at failures of the starter solenoid or starter motor itself. For that you are going to need a multimeter. If you don't have one go and buy a cheap one, it is a useful thing to have for diagnosing electrical problems.
  5. Just what cjvfr said
    PLUS if the battery is about 4 years old or more it could be stuffed too and give exactly the same symptoms a a loose connection. When dead some will exhibit a high internal resistance and be able to run small loads (lights etc) but not crank.
    get the multimeter and put it on the batt terminals, turn on ignition and ther should be a bout 12V still indicated. If it drops to below 10 (or disappears) whenyou hit the starter, the batery is stuffed. If it doesnt then you've got a bad connection or starter motor.
  6. not sure if this helps, what's said above covers it, have yo utried push starting?
    Sat morn prac session my bike would 'crank' so pushing the start button would not turn anything over, lights were on but no cranking, boys gave me a push no luck, ended being a shitty 'kill switch' I never use it always use key to kill and start. for some reason i flicked it once and that cacked itself. so after about 10 or so 'on n off' switches the bike started, might help you might not, one thing Doug mentioned, spray the bugger with wd40 and that should clean any muck as in water/dust and whi know what else. Good luck.
  7. thanks for the replies guys!

    okay so off to buy a multimeter and a new battery!
    will inform update with what happens

    @goddie yea ive tried push starting it nothing as well (or maybe me and my friend are doing it wrong :p)
  8. Buy the mutimeter and hold off buying the battery until you test the old one with the multimeter.
  9. sorry been busy with work and stuff
    anyways update!
    i bought a multimeter and check the voltage on my battery and it says 12v's
    i went to a bike scrap yard and picked up a relay and a ecu plugged them in and still nothing

    a few friends said to check the fuel levels and the carburetor
    full tank and carbie was clean
  10. MOST batteries will read 12V with NO LOAD on them. You need to also see what it says when you hit the starter. If it THEN drops below 10 the battery is stuffed. IF it doesnt drop when you hit the starter theres a problem with the starter relay or switch most likely.
    Thats about all I can do over the net ](*,)
  11. Lack of fuel in the carby will not affect spark.

    You need to be clear on what is stopping the bike from starting, if it is no spark, then fuel will not be your issue. If there is spark then it is a fuel supply problem.

    I'd be checking the battery under load, and change your fuses even if they look ok, they can fail without the fuse wire visibly breaking.
  12. with the kill switch on it drops about .2 volts (11.8)
    im considering taking it to the mechanic and dishing out another weeks pay out onto it haha
  13. First try the following:
    1. Make sure the multimeter is set to read DC Volts.
    2. Connect the multimeter across the battery and press that start button, What voltage does the multimeter show when the start button is pushed?
    3. Connect the multimeter with the negative (Black) on the bike frame and the positive (red) on the battery positive terminal, Push the start, what voltage?
    4. Measure between frame and positive of the starter motor, What voltage?

    You can see what we are doing here methodically working through the start circuit, ignore fuel for the moment, if it doesn't crank then fuel is not an issue at the moment. I know there is the temptation to just try different things but from what you have said it sounds electrical and these type of faults just take a step by step approach.

    Step 1 & 2 above establish if the battery is healthy and what load, if any is coming on the bike when you press start. Step 3 tells you if the negative battery bonding to the frame is intact. Step 4 tells you if voltage is getting to the starter motor when you press start, if yes, probably start solenoid, if no then probably starter motor.
  14. Nor will lack of fuel cause the bike to not crank over.

    However if it is not turning over, spark is also probably not the issue. Once you get it cranking if there is still no spark, you have an issue.

    Do what CJVFR says and report back.
  15. sorry i havnt been posting
    and informing you guys whats happening work is taking over <,<
    anyways i got my bike up and running
    a mate of mine came over to look at the bike when i wasnt home and said it was the starter motor
    and surely enough it was