Author Topic: CB 250 RS ELECTRICAL PROBLEMS  (Read 958 times)

xbally

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CB 250 RS ELECTRICAL PROBLEMS
« on: March 04, 2023, 07:55:10 PM »
Well , today I decided to venture forth on my RS......The engine started fine as usual and I got about a mile up the road before I realised neither the lights or indicators were working. Upon further checking none of the electrics except the ignition worked. I rode back home to check  and the fuses seemed OK as far as I could tell- I replaced them all just in case. The battery connections were secure so I'm suspecting the ignition switch. The parking light is the only light I can get to work (front and rear) in the third position on the switch. The engine will stop running when turned off at the ignition switch. I should also say recently I've added a permanent lead across the battery so I can use a the connector to run a heated waistcoat. I've had no trouble with this having used it about 5-10 times and it was working today? I'm not great with electrics so just looking for any clues as to what could be wrong please. A pattern ignition switch is very cheap so may be worth getting for a start?
HONDA CB250RSA HONDA ST70

iansoady

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Re: CB 250 RS ELECTRICAL PROBLEMS
« Reply #1 on: March 05, 2023, 10:10:33 AM »
Remember that the ignition is totally separate from the battery / lights etc so the engine will run regardless of battery state. Do you have a wiring diagram? According to mine, when the ignition switch is in the On position, wires red and black are connected, as are brown / white and brown.

As far as I can see the red wire is the positive feed from the battery, black is feed to ignition controlled stuff like the horn. Brown / white seeems to be input live for lights and brown output. I have a pdf copy of the manual with (almost illegible) wiring diagram if it helps.
Ian.
1952 Norton ES2
1965 BSA-Suzuki
1992 Yamaha SRV250

xbally

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Re: CB 250 RS ELECTRICAL PROBLEMS
« Reply #2 on: March 05, 2023, 11:24:44 AM »
Thanks Ian. I've cleaned up the battery earth this morning-there was a bit of corrosion but it was tight .I do have a Haynes manual thanks - with a wiring diagram. I've just stripped out the ignition switch as I suspect it's that. TBH they are so cheap (well pattern ones £15) that I think I'll get one anyway just in case-it's pretty grim where the wires attach to the posts on the switch terminals.
HONDA CB250RSA HONDA ST70

kevberlin

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Re: CB 250 RS ELECTRICAL PROBLEMS
« Reply #3 on: March 05, 2023, 01:37:35 PM »
Thanks Ian. I've cleaned up the battery earth this morning-there was a bit of corrosion but it was tight .I do have a Haynes manual thanks - with a wiring diagram. I've just stripped out the ignition switch as I suspect it's that. TBH they are so cheap (well pattern ones £15) that I think I'll get one anyway just in case-it's pretty grim where the wires attach to the posts on the switch terminals.
There’s a new one from Wemoto sat in my garage doing nothing.
Yours is you want it. FOC
Happy to post it to you.
Kev
1983 Honda CB250RS
2023 BMW G310GS

xbally

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Re: CB 250 RS ELECTRICAL PROBLEMS
« Reply #4 on: March 05, 2023, 05:17:35 PM »
Thanks for the very kind offer Kev.
I still have a few 250 RS parts to swap if you need anything?
PM me by all means.
Martin
HONDA CB250RSA HONDA ST70

kevberlin

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Re: CB 250 RS ELECTRICAL PROBLEMS
« Reply #5 on: March 05, 2023, 05:35:59 PM »
Thanks for the very kind offer Kev.
I still have a few 250 RS parts to swap if you need anything?
PM me by all means.
Martin
Martin,
PM…….possibly twice 😂
1983 Honda CB250RS
2023 BMW G310GS

tevie54

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Re: CB 250 RS ELECTRICAL PROBLEMS
« Reply #6 on: March 06, 2023, 09:28:39 PM »
I would suspect either the ignition switch or the light switch. From what I remember the pattern ignition switches have a different plug on the end so you have to cut one wire and bypass the plug or something like that.
Hope this helps

xbally

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Re: CB 250 RS ELECTRICAL PROBLEMS
« Reply #7 on: March 06, 2023, 10:02:24 PM »
Kev has sorted me out with the new ignition switch (many thanks) so I will fit that as soon as it comes. In the meantime I have removed the old one which looks very manky indeed. I've put my circuit tester to the main ignition switch feed from the battery and that circuit is live -so fingers crossed that will sort it out. ;D
HONDA CB250RSA HONDA ST70

xbally

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Re: CB 250 RS ELECTRICAL PROBLEMS
« Reply #8 on: March 09, 2023, 01:04:06 PM »
Success-it was the ignition switch-all working correctly again now it's been replaced thanks to Kex ;D
HONDA CB250RSA HONDA ST70

Moto63

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Re: CB 250 RS ELECTRICAL PROBLEMS
« Reply #9 on: March 10, 2023, 08:11:38 AM »
Success all working correctly again now it's been replaced thanks to Kex ;D
KEX... are those the special underpants that one wears on the outside of your trousers, bit like superman 🦸???😎

xbally

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Re: CB 250 RS ELECTRICAL PROBLEMS
« Reply #10 on: March 10, 2023, 10:50:00 AM »
Success all working correctly again now it's been replaced thanks to Kex ;D
KEX... are those the special underpants that one wears on the outside of your trousers, bit like superman 🦸???😎
Ooooooooops- I  really must check my spelling before hitting the post button.............Well  I'm very grateful to KEV (sorry) for kindly offering his spare ignition switch to me.   
HONDA CB250RSA HONDA ST70