Lucas Hazard Switches

[MadRiver]

Ok, who was the poor, tormented soul at Lucas in the late 1960s who was in charge of designing hazard switches? This cat was either a misanthrope, had deluded himself into thinking that making something simple into something complex was somehow an art form, or more likely, both. I recently took apart and rebuilt the original hazard switch on my 250, and I must admit, I was impressed with how many moving parts one could squeeze into such a small place. On the heels of that pleasing little diversion, the hazard switch on my MGC went on the blink. It featured a completely different design, but equally basking in complexity. No less than seven moving parts (or was it eight? I don't want to short change Dr. Lucas' minions.

The sad thing is I think I enjoy fixing them.

 

[DrEntropy]

And a goot thing, too!!! The 'white-box' repro ones are absolute garbage by comparison. Keep the originals as long as you can. RELAY the devices if at all practical and you'll have a much better chance.

 

[dklawson]

Your post is a timely surprise.

I spent last evening searching for online wiring diagrams to help an acquaintance in the U.K. sort out the wiring for his later model Mini's hazard light switch. Neither my Mini nor my Triumph have one so it was a very educational experience.

 

[MadRiver]

Good timing!

I must admit that I have very little experience with vehicles other than LBCs. I've always been curious if vehicles from other countries had a similar approach to wiring the turn signals through the hazard switch.

B.

 

[TR3driver]

In general, American cars do not wire the turn signals through the hazard switch. Instead, they use a more complicated turn signal switch that in turn allows the hazard wiring to be independant of the turn signal wiring (except for the actual wires to the bulbs/lamps).

In some cases this can lead to odd behavior; for example in many Chrysler products of the 60s & 70s you could listen to the radio with the key off, by turning on both the turn signals and the hazard flashers. The lights wouldn't actually flash as I recall, but the radio would play from the power fed through the hazard flasher and backwards through the turn flasher into the switched auxilliary circuit. But if you turned on the wipers, everything would flash ! (including the wipers)

 

[MadRiver]

In some cases this can lead to odd behavior; for example in many Chrysler products of the 60s & 70s you could listen to the radio with the key off, by turning on both the turn signals and the hazard flashers. The lights wouldn't actually flash as I recall, but the radio would play from the power fed through the hazard flasher and backwards through the turn flasher into the switched auxilliary circuit. But if you turned on the wipers, everything would flash ! (including the wipers)

That's fantastic!

 

[IanF]

The timeliness of this post is uncanny... I was thinking the same thing as I was reassembling the Spitfire's dash the other week with the new harness... I bought a "spiffier" switch fro British Wiring, but it won't fit in the OE dash and we don't have the new panels ready yet... and since we really didn't want ot use the bland, DPDT toggle hazard switch included with the kit, I decided to try to reuse the old one...

Yeah right...

After spending the better part of an hour looking at the diagrams trying to figure out how to combine the two, I decided "to heck with this..." and used the toggle...