Brake Lights Not Working On Split Screen

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xrsteve2003
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Brake Lights Not Working On Split Screen

Post by xrsteve2003 »

As title. I can't get the brake lights to work. I've checked the bulbs and there ok. Not sure where to look now. I don't think there​ is a fuse covering the lights. It's a split screen model . Any ideas where i could start?
Thanks
Steve
greendefender123
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Re: Brake Lights Not Working On Split Screen

Post by greendefender123 »

Power to the brake light switch. Then power through whilst the pedal is pressed.
palacebear
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Re: Brake Lights Not Working On Split Screen

Post by palacebear »

There is a fuse. Same one that protects wipers and indicators. If they're working then look at the brake light switch. Might be faulty. Might simply be a broken/disconnected wire or poor connection at the switch. May be worth checking in the boot in case something like a rogue tool-roll or improperly secured spare wheel has caused any wiring damage
Last edited by palacebear on Thu Jul 13, 2017 10:26 pm, edited 1 time in total.
1956 4-door called Max
xrsteve2003
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Re: Brake Lights Not Working On Split Screen

Post by xrsteve2003 »

Sorry to be thick but how do you get at the switch at the pedal?
firedrake1942
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Re: Brake Lights Not Working On Split Screen

Post by firedrake1942 »

Not sure about the MM but the brake light switch is in line on a brass 4 way union (sometimes with bush on sometimes screw on terminals) with the brake pipes. On later models it is to the LHS of the radiator in the engine compartment

https://www.google.co.uk/imgres?imgurl= ... mrc&uact=8
palacebear
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Re: Brake Lights Not Working On Split Screen

Post by palacebear »

Same on my Series 2. Down in the depths on the drivers' side of the radiator. Don't remove the switch unless you need to otherwise you'll have some brake bleeding to contend with as well.
1956 4-door called Max
liammonty
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Re: Brake Lights Not Working On Split Screen

Post by liammonty »

The switches do fail - especially the new ones, which aren't great quality. As an aside, I must have replaced 10 of these over the years, and never once have I needed to bleed the brakes afterwards.
xrsteve2003
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Re: Brake Lights Not Working On Split Screen

Post by xrsteve2003 »

Great. Thanks guys.
Steve :)
Budgie
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Re: Brake Lights Not Working On Split Screen

Post by Budgie »

palacebear wrote: May be worth checking in the boot in case something like a rogue tool-roll or improperly secured spare wheel has caused any wiring damage
This happened to my tourer a few years ago. The spare wheel was chafing against the wire and caused the insulation to wear through and the brake lights to become intermittent.
Trickydicky
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Re: Brake Lights Not Working On Split Screen

Post by Trickydicky »

To test the circuit simply disconnect the two connections on the switch, connect them together and the lights should light up, this will prove if it is a switch problem or a circuit problem.
Richard

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neilmorey
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Re: Brake Lights Not Working On Split Screen

Post by neilmorey »

Can't be sure yours is the same pressure operated brake light switch but mine went last year and reading up it is a common problem.
Advice I read at the time was to wrap area around the switch with rags and quickly swap the switches over. You'd loose a lot more fluid if you have a high level remote brake fluid reservoir but air getting in wouldn't be an issue. The switch can be bled through the threads of the connection by getting an assistant to gently press the pedal whilst fully tightening up. It works and my switch was changed with no air in system.
I have also fitted LED rear bulbs which are expensive but reduce the switched current and therefore risk of the switch contacts burning out.
http://www.moss-europe.co.uk/led-bulb-b ... 380lr.html
palacebear
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Re: Brake Lights Not Working On Split Screen

Post by palacebear »

neilmorey wrote: I have also fitted LED rear bulbs which are expensive but reduce the switched current and therefore risk of the switch contacts burning out.
http://www.moss-europe.co.uk/led-bulb-b ... 380lr.html
I like the idea of LED stop/tail bulbs. Moss catalogue states 'negative earth only'. If correct, is there a source of positive earth LED bulbs anywhere?
1956 4-door called Max
colin addison
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Re: Brake Lights Not Working On Split Screen

Post by colin addison »

www.dynamoregulatorconversions.com do positive earth light boards for the Lucas MM rears. I fitted these to mine to reduce the load across the switch and they work well.
Colin
palacebear
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Re: Brake Lights Not Working On Split Screen

Post by palacebear »

Thanks for that Colin. I recently got my self-flashing trafficator LEDs from the same guy. Was pleased with his.quality and dispatch time. Will have a look at his website again :)
1956 4-door called Max
dockerman
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Re: Brake Lights Not Working On Split Screen

Post by dockerman »

Trickydicky wrote:To test the circuit simply disconnect the two connections on the switch, connect them together and the lights should light up, this will prove if it is a switch problem or a circuit problem.
Hi Trickydicky i have also problems with one brake light on me splitscreen the o/s works and the n/s is inop i have tried connecting the two wires together and the brake lights dont come on does that mean the switch is at fault or their is a fault in the circuit
Thank you
Trickydicky
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Re: Brake Lights Not Working On Split Screen

Post by Trickydicky »

From your description it sounds like a earth problem, the earths for the rear lights are attached to the bumper mounting brackets in the boot. Check they are clean and secure.
Richard

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dudload
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Re: Brake Lights Not Working On Split Screen

Post by dudload »

I had a similar problem and it turned out to be that the clip in the light itself was loose and needed tightening up. When putting the light back in it would wiggle out and short against the bodywork, I tested the switch, calling earth points but it turned out to be something really simple
dockerman
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Re: Brake Lights Not Working On Split Screen

Post by dockerman »

Thanks for the feed back
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