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Horn/ammeter issue

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Can anyone help with this? '55 ES2 with standard combined horn/dip switch. When I press the horn button the horn (sort of) beeps (almost inaudible unless bike is running) and the ammeter flicks across to the +ve side. I think I should be looking for a short between the feed from the horn button to the horn and the connection from 3 on the lighting switch to the ammeter. But I'm no electrician. Any clues? BTW the return from the horn to the ammeter is connected to the other side and then on to the-ve side of the battery. Very grateful for any help. George
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Previously George Phillips wrote:
Can anyone help with this? '55 ES2 with standard combined horn/dip switch. When I press the horn button the horn (sort of) beeps (almost inaudible unless bike is running) and the ammeter flicks across to the +ve side. I think I should be looking for a short between the feed from the horn button to the horn and the connection from 3 on the lighting switch to the ammeter. But I'm no electrician. Any clues? BTW the return from the horn to the ammeter is connected to the other side and then on to the-ve side of the battery. Very grateful for any help. George

Hello you are an engineer if you press horn your using electric so the ammeterresponse with the use of electric used and if you cannot hear the horn then fit one you can hear like an air horn you can get them to play tunes yours Annaj
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Quite right Anna. I am, albeit a mechanical services engineer. But even as a mechanical engineer I know that the horn does not pass through the ammeter but by-passes it. (Check the wring diagram). Hence my query. George
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Sounds like a short from a live wire before the horn. The horn button is always live after the voltage has passed the horn itself, and the horn button completes the circuit as it sends it to earth. If the ammeter flickers, then there must be power reaching the hornfrom a metered circuit before the wire even reaches thehorn. If live reached the wire after the horn, it would short out straight to earth as soon as the horn button was touched.

Unless the horn is wrongly connected to the ammeter terminal o the output side beyond the battery rather then the input side before it.

Is there a loose wire whisker at one of the terminals inside the headlamp shell? Using the switch as a junction box (as they do) makes it all too easy to wire it up wrong! I'm sure mine is wrong because the ammeter always shows discharge but my battery never goes flat...

If all else fails, I'd blame it on a dodgy earth...but with no idea why that can give such strange results

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I'm still absorbing all that David, Many thanks. Don't forget it's positive earth, so rather than sending the power to earth it takes it from the earth. But I take your point about the power reaching the horn from a metered circuit. I have checked the connections on the light switch. In fact I've had it all out and it seems OK. The horn circuit is: earth to button; button to horn; horn to "outlet" ie negative side of ammeter; ammeter to negative battery terminal. My view is that if there were a short after the horn across to the "inlet" side of the ammeter it would cause the ammeter to twitch and the horn would still work? G
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Hi George - let's hope Al Osborne turns up here soon! Does the wire from the horn go straight to the negative side of the meter, or does it (for some odd reason) make an excursion via a terminal on the switch? If so, maybe there is something odd about the switch -and the horn is getting some of its power from both sides of the ammeter? The place I wonder about is the combined horn/dip switch - but that's only live when the headlight is on so that shouldn't be the issue.

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Previously George Phillips wrote:
Quite right Anna. I am, albeit a mechanical services engineer. But even as a mechanical engineer I know that the horn does not pass through the ammeter but by-passes it. (Check the wring diagram). Hence my query. George

Hello George the horn wire is connected to the B+ side of the ammeter to number 2 switch and then blue wire out to dip switch and horn button from there it runs in a brownand black wire to horn on the positiveside and a black wire from the battery on the negative side so if you press the horn button the ammeter will pick up of any battery drain on put uponit!! Your kindly annaJ
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Sorry Anna but on every Norton wiring diagram I have the horn power doesn't run through the ammeter. Of course the PO might simply have attached it to the wrong ammeter terminal...not that it matters anyway, does it? No harm done either way.

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battery might need a charge as you say it works when bike is started so i don't think its shorting .unless the horn has given up needing more amps to work it .

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Thanks to all of you for your interest. Just to answer a few points - David, the wire TO the horn comes from the horn button and the wire FROM the horn goes to the +ve side of the ammeter and then direct to the -ve battery terminal. Anna - colour codes are irrelevant on my bike as, being 60+ years old, they are a jumble of old and new. Nevertheless,the horn does not connect to the lighting switch either on the bike or on the wiring diagram. Barry - I'll check the battery today but that doesn't explain why the ammeter flicks into the +ve area when I press the button?All very interesting! George
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Previously George Phillips wrote:
Thanks to all of you for your interest. Just to answer a few points - David, the wire TO the horn comes from the horn button and the wire FROM the horn goes to the +ve side of the ammeter and then direct to the -ve battery terminal. Anna - colour codes are irrelevant on my bike as, being 60+ years old, they are a jumble of old and new. Nevertheless,the horn does not connect to the lighting switch either on the bike or on the wiring diagram. Barry - I'll check the battery today but that doesn't explain why the ammeter flicks into the +ve area when I press the button?All very interesting! George

Hello George Will the wiring Diagram I have here is for my 1954 featherbed Model 88 Dominator which terminal number 2 has two wire coming from it one goestoo the dip switch and the other one goestoo the ammeter +plus side I should know has I wired the Bike myself and my Norton 650 Manxmanis the same set up but an SA41 lighting switch were has the Model 88 is a U34 lighting switch, but since I looked at my many wiring diagrams I found out that you are right mate your is wired so it does not go thoughthe lighting switch it comes directly from the battery has dosed the BSA A10 Posted wiring diagram yours , Anna JAttachments nortones2-jpg-jpg
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George: Have you tested the horn itself? Remove the horn and the battery and run some test wires direct to the horn from the battery. Maybe the horn is defective?

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I have arrived! !) Ignore any words from AJD there is no electrical knowledge there.The point that the Ammeter flicks the wrong way is totally correct.First the ammeter rule-there is a charge circuit to the Ammeter, there is a discharge circuit (lights, ignition) and there is the battery. The rule is the battery is on its own. The other two two go together.Now we brake the rule!! The horn and the stop light (on Dommie or such) can go direct on the battery as A) they have intermittent usage, B) the horn at least can have high current not too good for Ammeter.Now the phenomenon of the ammeter going the wrong way, this is because the engine is running and the horn power is coming from the generator not from the battery. If this doesn't explain it then give me a call some time or look closely at the wiring diagram. In fact when you are riding along if the Ammeter flicks 'charge' when the stop light is activated, this is a handy check that the stop lamp is working.
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Right - some checks carried out. Thought I'd answer via this thread rather than call, Al, lest there's someone out there with similar ghost problems.1) Horn checked with external battery - OK2) battery voltage checked (no load) 7.2V3) Horn button pressed no engine, almost no beep, ammeter flicks to +ve.4) Horn button pressed, engine on tick-over, no beep, ammeter flicks to +ve.5) Horn button pressed, engine on high revs, horn works, ammeter flicks to +ve 6) engine off, brake light activated, ammeter flicks to +ve.So in a nutshell, Al was of course correct about the flicking to +ve although I can't understand why it does that with the engine not running.Other than that I think I've been tilting at windmills. I've been chasing a fault that doesn't exist. Very grateful for all the interest and input. Hope it's been of use to someone out there. It certainly has for me. George
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Previously alan_osborn wrote:
I have arrived! !) Ignore any words from AJD there is no electrical knowledge there.The point that the Ammeter flicks the wrong way is totally correct.First the ammeter rule-there is a charge circuit to the Ammeter, there is a discharge circuit (lights, ignition) and there is the battery. The rule is the battery is on its own. The other two two go together.Now we brake the rule!! The horn and the stop light (on Dommie or such) can go direct on the battery as A) they have intermittent usage, B) the horn at least can have high current not too good for Ammeter.Now the phenomenon of the ammeter going the wrong way, this is because the engine is running and the horn power is coming from the generator not from the battery. If this doesn't explain it then give me a call some time or look closely at the wiring diagram. In fact when you are riding along if the Ammeter flicks 'charge' when the stop light is activated, this is a handy check that the stop lamp is working.

In answer this statementI have wired up a number of Norton's and BSA's Honda's and Suzuki's but after each one, they all worked right and even pass M.O.T's how do you account for this with no electrical knowledge then ! and even my Norton 650 Manxmanwork right and there are no wiring diagrams for this Has the ones in the Haynes manual for Norton twins is the wrong one for this model. And upgraded it to 12volts yours annaj
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Barry - I haven't actually checked but it look and sounds like a normal 6V unit. I'll have a look on the back of it today just to be sure.
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Keep posting Anna, Some forums are so deadly dull that no one posts for months, You do have usefull and relevant information tucked away and an obsession with a rare old blue Norton,(no where near as rare as a 650 DL!) we are all a bit odd one way or another and I hope we are all mature enough to make allowances for the health problems that us oldies face.

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Odd, but my later, 1960, Norton Owners manual shows the horn feed being taken direct from the -ve terminal of the battery for the ES2 and model 50 with , in the case of the 88 and 99 and the earlier model 7 the feed comes from the + terminal of the ammeter .

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Barry - no indication of the voltage on the horn. But with the engine running it sounds like your standard mid-fifties hooter. Also when checked with an external 6V fully charged battery it sounds fine.
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at least you know the horn is ok .have you a main fuse on the battery. that would blow indicating a fault /short ect. i am not an electrical expert just trying to help.

Barry

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Previously George Phillips wrote:
Right - some checks carried out. Thought I'd answer via this thread rather than call, Al, lest there's someone out there with similar ghost problems.1) Horn checked with external battery - OK2) battery voltage checked (no load) 7.2V3) Horn button pressed no engine, almost no beep, ammeter flicks to +ve.4) Horn button pressed, engine on tick-over, no beep, ammeter flicks to +ve.5) Horn button pressed, engine on high revs, horn works, ammeter flicks to +ve 6) engine off, brake light activated, ammeter flicks to +ve.So in a nutshell, Al was of course correct about the flicking to +ve although I can't understand why it does that with the engine not running.Other than that I think I've been tilting at windmills. I've been chasing a fault that doesn't exist. Very grateful for all the interest and input. Hope it's been of use to someone out there. It certainly has for me. George
1-6 tests above=observations-1)OK 2)sounds a bit high, unless engine is running in which case it is correct.3)/4) does not make much sense would have to check over the phone to find out what is going on. 5) This is fine if horn is connected straight to the battery. 6)This is the same oddity as 3/4).Now, IF the engine is NOT running, and the stop and horn are wired direct to the battery, when they are operated then the power comes from the battery direct to the horn/stop it cannot come through the ammeter. unless there is a strange fault/miss-connection.I think we need to talk George.Al
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Thanks Al. I'll consider that lot in the morning and give you a call during the day.Many thanks - George
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Previously robert_tuck wrote:

Keep posting Anna, Some forums are so deadly dull that no one posts for months, You do have usefull and relevant information tucked away and an obsession with a rare old blue Norton,(no where near as rare as a 650 DL!) we are all a bit odd one way or another and I hope we are all mature enough to make allowances for the health problems that us oldies face.

Hello ROB the 650 de-lux is a very nice bike even I would not mind one mayself or the Norton grey 650 standard But I just must say this the first 650 the Norton Manxmanwas top of its class and a fantastic bike to own and ride its like it was made just for you !!! I have privet information where the first one to be built is hiding and is up for sale But I have no indicationof what the owner wants in cash terms for this machine, but I do have his contact details Yours Anna J
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AJD is off topic again.

George let me know the results of our phone call, I think a lot will improve once you get the battery charging properly.

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Hi Al - et al - A double check on the battery voltage gave a reading of 6.3. In attempting to trace the "fault" I managed to disable the main/dip bulb. When I pushed all the cables back into the h/lamp shell in disgust, the bulb suddenly worked. I'm off to the IoM at the end of August so have decided to live with this strange anomaly (the horn) until I get back in September. After all, we're not supposed to use the horn when stationary anyway! I'll continue to ponder it but I'm not going digging into the wiring for fear of causing more damage. It will become one of my winter projects. George

 


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