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MG MGB Technical - Hazzard Warning Rocker Switch

What is the off position for the hazzard warning switch on a 1979 MGB ( fed. spec car). Turn indicator lamps work, but hazzards are a no go. Power is present at the hazzard switch, but not at the hazzard flasher behind the glove box.

Cheers, Davy Crocker
Davy Crocker

Davy,

There has been some discussion on this subject re. my 73B on the post below titled "Funky Turn Signals".

Not a complete answer but a bit of info.

BH Davis
BH Davis

PS:

The hazard switch on mine is listed in Moss as 73 to 76. Off is when the lighted end (top) is depressed and on is when the lighted end is raised.

BH
BH Davis

Davy. Switch is off when the bottom is pressed inwards. Switch is on when the switch is pressed at the top of the switch.

Les
Les Bengtson

Davy. Screwed up completely. Only defense is that I had been driving a non-air conditioned MGB in 109 deg F (42 deg C) heat. I posted the exact opposite of the correct orientation. Checked when I, again, had to go out.

When the upper end of the rocker, the one with the "hazard" label on it, is pushed towards the dash, the switch is off.

When the lower end of the rocker, the one without marking, is pushed towards the dash, the switch is on and the hazard warning lights flash. This was on a 79B which has the same dash as yours.

Sorry for the mis-information.

Les
Les Bengtson

The hazard switch gets power from two sources. A green wire to power the turn signals and a lightgreen/brown wire from the hazard flasher to power the hazard lights. The hazard flasher has brown and lightgreen/brown wires connected to it. The turn signal flasher has green and lightgreen/brown wires connected to it. The brown wire for the hazard lights is the only fused brown wire in the car. If the brown wire going to the hazard flasher doesn't have power, check the fuse.

Wiring diagrams are available at http://www.advanceautowire.com click on stock schematics. Make yourself a couple of enlarged copies.
Kimberly

To add to what Kimberley has said, when the hazard switch is off just two of the six (possibly just five) terminals are connected together, and the two greens for the turn signals are connected to these. The other four (or three) are isolated. When the hazard switch is on the first two are now isolated, and the other four (or three) are connected together, that is light-green/brown (from the hazard flasher), green/red and green/white to the lamps, and possibly light-green/purple to the hazard repeater lamp. Not that you really need this last as the turn signal repeater lamps flash with the hazards anyway.

Whereas there should be 12v present (ignition on) at *both* terminals of the turn flasher, unless they are actually flashing, there will only be 12v (all the time) at one terminal (B) of the hazard flasher and this should have the brown wire on it. There wioll only be voltage on the other terminal of the hazard flasher (L, light-green/brown) when they are actually working.
Paul Hunt 2

This thread was discussed between 20/07/2007 and 21/07/2007

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