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MG MGB Technical - Hazards etc. not working

First time that I have been in this forum. I have to get some of your collective expertise. I have just acquired a 73 MGB and the Hazard lights do not work , and I need that for a safety certificate. Not only do the Hazards not work but neither do the Cigar lighter, and the fasten seat belt lamp. I notice that their is an in-line fuse in the console and I wonder what it fuses.

I have looked at wiring diagrams till my eyes are buggy. I am sure that there are multiple small problems, and I am going to try and delve into them today. Any help would be appreciated.
C.R. Tyrell

hi, welcome,
yes check the in-line fuse and check all other connections, wires and earths are clean, secure and protected

the three are separate so unconnected other than the causes could be the same or similar

others who know what they're talking about will be along later

IF you should need a new hazard switch a good working s/h unit could be better than a newly made unit as that could be one of the p*ss poorly made modern parts we suffer from - or perhaps an electronic replacement

have a look at Paul Hunt's site mgb-stuff for colour wiring diagrams and loads more info -

Nigel Atkins

Great start for info Nigel. Looks like a new replacement switch in there already... could be faulty. Just got into it. Bulbs missing etc. Shees!

Got a wiring diagram from Bently? Anyway, much easier to read.
C.R. Tyrell

Download a wiring diagram from here:

Have it enlarged and laminated. You'll refer to it often!

Dan Hiltz

Right hand inner wing - bottom fuse in box does the purple circuit which is cigar lighter and seat belt lights then in line fuse just under the fuse box is the hazards
Chris at Octarine Services

Thanks Dan.... did that, helped immensely. Chris.. thank you. Found the major problem... new switch was broken in the inside and not making any contact with anything, but bridging the green for the directionals. Thanks all... now I just have to persevere.
C.R. Tyrell

On UK cars at least the in-line fuse under the fusebox connects white/green to green/pink and is for the wipers, heater fan and electric screen washers of 71 to 74 4-cylinder cars and all V8s.

The hazards in-line fuse connects brown to brown and on my UK 75 at least is very conveniently located behind the centre console. This may have moved to under the fusebox on 74 1/2 and later cars.
Paul Hunt

>>new switch was broken<<
which switch is that please CR so that I can add it to my list?

couple of points you probably already know by now, never assume a new part or component works or fits correctly and never assume that a part or component already on the car is original type or is the correct part or component or is fitted correctly or is fully working correctly, biggest problem with most cars is the previous >>bulbs missing<< and often present owners and their lack of proper care for the car but hopefully you'll not be in that group

just for your info, if you want to you can change your shown name and add a link to your vehicle profile

as your car is a Canadian model(?) it might vary from UK and US models and there are quite a few wiring diagrams that cover a 1973 or 73 model year car so you might be better to pin things down by 'chassis' number
Nigel Atkins

Nigel; The car originated in California, then to Arizona in the U.S. then to Ontario Canada. I did find the appropriate wiring diagram for the car and that helped immensely.

The broken switch was in the car when I purchased it (Hazard switch) and is the proper one for the car as far as I can tell. It is 6 round pins and matches the socket, which is original to the harness. The switch failed at the plastic of the rocker where the spring loaded pins are set in. The plastic broke away on the side of one pin resulting in a "jam" which bent the sheet brass contact. I am presuming the switch is a newer replacement as the white lettering is not rubbed of and the chrome escutcheon looks new.

I guess I should update my vehicle profile. I had two MG's in the garage now there are three.... guess I parked them too close. They are breeding like rabbits.
C.R. Tyrell

good stuff CR, I thought you might be new to all this but obviously you're not, I hope you get time to drive all three enough, you either enjoy MGs or a sucker for punishment :)

I was thinking that the switch might be a very recent one of poor quality - to add to the list but it might not be that recent

chrome escutcheon ! these U.S. cars are so bling :)
Nigel Atkins

Nigel, I am kinda new to the LBC's only since 2011. It is a sickness I have, but I am afraid to seek therapy in case I got 'cured" then I wouldn't have any fun anymore. I drive all three all summer long. A little over 5000 mi. on the TD last year. Presently restoring my MGA 1500. Which will be on the road end of April.

The "B" is driving me a good way.
C.R. Tyrell

CR you are getting better - you've gone for a soft modern MG

... well in relation to the other two anyway

try to extend the summer season as much as you can for all three as this will help with your mitigation should a therapist be forced on your and given enough justification you might convert the therapist !

good luck, happy and safe motoring
Nigel Atkins

This thread was discussed between 22/02/2014 and 24/02/2014

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