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MG MGA - Brake light switch

I realised today that my brake lights aren't working ... and the culprit is the pressure switch. There are a few archived threads on the subject which I've just finished reading, but most include warnings about poor quality replacement parts. Has anyone fitted one recently that they would recommend (or alternatively that I should definitely avoid)?
Many thanks in advance.
Robert Sinclair

Get the one from Ron Francis in USA. Much better quality than those offered by Moss etc. It has a different connection on top, but can be easily modified. Have been using his switches for years.
Gary Lock

We have had reported failures of theh Ron Francis switches as well.

For known good and bad switches see here: http://mgaguru.com/mgtech/electric/et119a.htm

I went through eight different bad ones (typically 5000 to 8000 miles each) in one year before I found a good one. In the past three years I now have 113,000 miles on a Autozone/Duralast RB401 switch. However, his part number may since have gone from good to bad, so it may depend on the production date of the switch.

I have one Park Remax switch, new old stock, that is said to be a winner, but haven't had the opportunity to test it yet.

I have lots of pictures of failed switches cut open to show the burned contacts. They all look the same, bad contact design.

I have a cut-open picture of an much older Lucas Switch (date code 8/65) that failed in the closed contact position. This is what a good switch should look like inside: http://mgaguru.com/mgtech/electric/et119g.htm

Some time in recent years the world has forgotten how to make a good switch. The only way we will ever reverse this situation is if we collectively refuse to buy the bad switches. For this to happen we need to identify most all of the bad ones, and at least one good one that we can actually use. So if you have a failed switch, send me the manufacturer's name and part number, and I will post it on my web page. And if you have a known good switch, send me that information as well, so the world can know where to buy the good ones.
barneymg

The Duralast switch is pretty good, but I had the threads fail on an MGB using one. Started leaking fluid badly. The switch itself was still functioning perfectly though.

The Ron Francis SW-32 is a good switch, but there aren't any out there that are as good or durable as the originals.
Steve Simmons

I believe that the current manufactured pressure brake switches should be completely discarded.
Use a simple non-pressure switch operating on the brake pedal lever as on Triumph cars.

Mick
M F Anderson

I found some N.O.S ones on the internet from a place in the UK that sells army surplus parts, cant remember the address but they are in LITCHFIELD, and they were a very good price, I bought 3.
Andy Tilney

I'm with Mick; fit a mechanical switch. I did, using the pressure switch to plug the existing union, plus I used a relay too so the switch should last.

Recently I was following another A with no brake lights. This had only just had a new switch fitted and the brakes only lit up with a really hefty push on the pedal. Mechanical switch now in place!

Regards
Colin
Colin Manley

All this talk of switches prompted me to check. Mine weren't working! Got a new SL134 from NAPA. Keep my fingers crossed.
Art Pearse

I am lucky in still having an *original* Lucas one, and LED lighting, so it should last forever

Dominic Clancy

Mine is the original as factory fitted! Not a bad record - from 1960. I have never touched it. Fingers crossed!

Barry.
Barry Gannon

I'm really reluctant to tell you guys this, given all the helpful comments, but when I went to remove the unit I discovered that one of the contacts was loose,so I tightened it up and, hey presto, I've got brake lights again. Hopefully it will now keep working for another 62 years (not that I'll know!)
Robert Sinclair

Its strange you should say that Robert,
what I thought was a faulty brake light switch on my MGA also turned out to be just a slightly loose connection and when I tightened the screw, everything worked just fine again.

The odd thing was that by the time discovered this, I had already fitted a mechanical switch that worked from the brake pedal.
I had connected this in parallel with the original switch using the screw connections on that switch and that is when I discovered the loose connection.

However, for some reason with both switches connected in parallel, the brake lights didnt work???

As soon as I disconnected the mechanical switch and went back to using just the original switch, then the lights worked fine!!!

I have checked the electrical operation of the new mechanical switch and it seems to be perfect??

So for now I will continue using the original switch and keep the mechanical switch in place to connect and use as a reserve if the original switch fails.

Colyn

Colyn Firth

Sure they weren't in series?
Art Pearse

Art, I just connected a wire from each side of the new switch to each of the screw connections on the original brake light switch.

I believe that is in parallel, unless I have misunderstood how the brake light wiring works. :-)

Cheers
Colyn
Colyn Firth

I did the mechanical switch years ago after fighting with pressure switch and its replacement. I wouldn't even bother to replace the pressure switch and would just replace it with a mechanical switch. Nobody can see it anyway.
Bill Haglan

“Art, I just connected a wire from each side of the new switch to each of the screw connections on the original brake light switch.

I believe that is in parallel, unless I have misunderstood how the brake light wiring works. :-) “

Yes, that is parallel, and it should have worked. Even in series, it should work as long as both switches are good.
Dave O'Neill 2

Colyn, didn't mean to insult your intelligence, but it was a possibility.
Art Pearse

No offense taken Art.

To borrow the motto of one of your North American colleagues on the MG Experience Forum, I'm "Always certain, often wrong!" :-)

Cheers
Colyn

Colyn Firth

If you are quick here's an NOS Lucas one

https://www.ebay.co.uk/itm/BMC-AUSTINMORRIS-MG-WOLSELEY-RILEY-JAGUAR-LUCAS-HS2-HYDRAULIC-BRAKE-SWITCH-NOS/173486440310?hash=item286498ff76:g:U74AAOSwzQdbcwFm

Dominic Clancy

Interesting that this thread should be started at this time. I have a '62 MGA Mk. II and a '53 MG TD. I installed a third high brake light on the TD and discovered that my brake lights came on only with very heavy pressure on the brake pedal. Off to NAPA for an SL144 switch but, while preparing to install the new switch I discovered that the battery ground strap to the POS terminal was loose. Tightened that up and all is working well with the old (also a NAPA SL144) switch.

See: "Thread: Brake light switch on pedal" on the TD-TF side.

Jud
J. K. Chapin

I take it the brackets for the electric pedal switch conversion are homemade.

Mick, Colin, Bill, or others: Care to send a photo of the bracket?
thanks,
Tyler
C.T. Irwin

Here is my collection of past failures since 1993. The 2 on the right were the best made.
Tyler


C.T. Irwin

This thread was discussed between 07/09/2018 and 28/10/2018

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