Power Problem

captain jack

Turbocharged
Joined
Oct 10, 2009
Messages
874
Location
UK North West Cheshire
I've just fitted a new battery which seems in good condition. The bike has just been returned from France where it suffered a broken Detent spring but last I saw of it was being ridden when the pick up truck collected it. After 3 weeks I know the battery was flat as my tracker told me so. On return the battery was completely flat 0.00V & would not take a charge, hence the new one. I now have power to all devices & the instrument sweep is good but there is no power to start the engine. I've checked the obvious ie kill switch, clutch switch, & starter relay, but there is no power to even pull in the starter relay. Looking at the wiring diagram there is only the start button which I had out & cleaned only a few weeks ago & then the ECU. Any ideas on this? I really don't want to even consider the ECU being faulty.
 
I know well-intended warp9.9, (& also recognize it was already posted) but I hate seeing that bypass info posted publicly on the forum
It's essentially a "Here's how you steal a Rocket" guide.

The headlight question is a good one - important piece of data (as is the year/model of the bike so we can match up the schematic):
SO - are the headlights on?
Do they go out when you press the start button/Pull the clutch?
What is the battery voltage with headlights ON?

Is there an alarm fitted?

Possible culprits are:
Bad Key-Switch
Open Fuse 9
Clutch switch
Start Switch
Starter/Headlight-cut relay.

You really need to break out your meter and follow the signal path (all voltages per red probe with black on battery negative)
1. Do you get 12V at both sides of Fuse 9?
2. Do you get 12V at the starter/headlight relay, on the Blue/Yellow wire?
3. Do you get 12V at the starter/headlight relay White/Red wire when you press the start button? (clutch not required for this test)

Connect Red probe to battery positive, test with black probe:
4. Do you get 12V at the starter/headlight relay yellow/brown wire when you pull the clutch lever?
 
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Well thanks to both DEcosse & Warp 9.9 for the replies. Firstly the details you were asking:-
1 it is a 2009 classic
2 it is fitted with a Datatool alarm/immobiliser
3 it is fitted the the Eastern a Beaver system with separate switch which was in the off position.
The rest I haven't got around to because as soon as I switched the lights to the on position so I could measure the terminal voltage, the bike fired up no problem, best start I've had out of her for a long time. Now I don't know what has caused this but I'm more than happy with the result. My only only concern is that it is charging at 12.58v ( I expected more) & the terminal voltage at rest is only 12.1v, I have been told by my dealer that the ECU won't allow starting at less than 12.3v. I'm hoping that someone can throw some light on it but so long as it keeps starting I'll be happy. Just been back to it, I now find that it will start with lights off but will not start with lights on. The battery voltage with lights off is 12.32 & with lights on voltage is 12.1v. Maybe this below 12.3 is right. Hope it helps, probably hinders.
 
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Correct, the bike will not start if the voltage is too low - the same interlock from the ECU to the starter/headlight relay is common to both low voltage and clutch switch, therefor the symptoms are same.
You may have just got lucky in that it saw sufficient voltage at the time you pressed the button on this occasion.

If it is at 12.58 with engine running, then you have a generator problem (either the stator or the R/R)
But also note that if your resting voltage is only 12.1 then your battery is not in great shape, especially if it is supposed to be 'new'
 
Thanks again DEcosse, I follow what you say & in similar thinking I have left the battery on the optima the overnight. This morning I checked all voltages including charging volts but unfortunately I got talking after that & promptly forgot them, the main thing being though is that I can remember that they were all good. The bike is now starting first time every time with or without lights on. I think I remember 12.52 v with lights on & 12.89v with lights off, when I've grown extra hands tonight, I'll check voltage at starting, but thanks for your help on this & the main thing is that it is now starting.
 
Your battery appears to have charged properly, however you really need to check that running voltage again to see whether indeed you have a generating system issue.
 
Just taken more voltage readings after bike at rest for 8 hrs :-

1. At rest. -------------------------- 12.94v
2. Ignition on/lights off ----------- 12.44v
3. Ignition on/lights on ------------ 12.21v
4. At start lowest reading noted -- 12.03v
5. Running ------------------------- 14.08v

Bike starting fine now still with lights on or off, my only concern is the voltage drop with ignition on but lights of, it seems a big drop in voltage for what believe to be minimal draw on the battery.
 
OK generating system good

Depends when you measure the voltage - within first few secs of ignition on the pump mm is running and that is not insignificant
Also, the off-load voltage is meaningless - you are just measuring float charge which is why you want to measure with some load applied
 
Thanks again for taking the trouble, the voltage taken with ignition on was immediately after turning ignition on. I am assuming that the pump you refer to is fuel, & yes I had forgotten that.
 
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