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MGB Mgb turn signals

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Carlbanan56

Carlbanan56

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Hi, I have some questions about the turn signals on my mgb 1975. Neither my turn signals nor my hazard lights seem to be working. I have only tried the signals with the engine turned off due to the extreme cold here in Sweden right now, don't know if that has an impact. I am a bit clueless about where to start. Most of what I have read online seems to be going into a problem where the turn signal does not work but the hazard lights do. The turn lever is also very hard to maneuver. Where should I start?
 
start by checking your ground wires. They are always black and most of the time that is the problem. There is an issue with the hazard lights/signals but, there are other things to check first

do you have a manual with a wiring diagram?
 
JP is right - the grounds are always a bit suspect so a logical 1st place to check. I even went so far as to do a high temp solder of a ground wire onto every lamp fixture - solid grounds clean up most of the infamous Lucas electrical gremlins.

Using the hazard lights should work regardless of whether the engine is running or even if the key is in the car. Turn signals should work with the key on, even with the engine not running.
 
You need a wiring schematic. This is a more complex system once the emergency flashers where added.
For starters, there are two flasher units fitted and usually an in-line fuse fitted to the power lead of the emergency flashers.
 
I will check all the grounds. I should have mentioned it earlier but when I got the car it had not moved for 25 years. During this time the grounds could gone bad. Which ground should I check? Maby a dum qustions but where do I find them?
 
No dumb questions here!

Start at the lamps. Should be a ~cluster~ of black wires connected to the body, front and rear. The rear one, I believe, is along the back of the boot (trunk). Don't remember exactly where the front one is, but have a look near the harness where the wires come out of the sheath and follow the black ones. Disassemble the connections and clean each ring terminal, along with the area of the body where it is attached. Put it all back together and after screwing it back in, smear on some dielectric grease to protect it.

And while you're at it, go ahead and disconnect all the positive wires' bullet connectors and clean them up as well.

Hope this helps!
 
Carlbanan56 said:
Hi, I have some questions about the turn signals on my mgb 1975. Neither my turn signals nor my hazard lights seem to be working. I have only tried the signals with the engine turned off due to the extreme cold here in Sweden right now, don't know if that has an impact. I am a bit clueless about where to start. Most of what I have read online seems to be going into a problem where the turn signal does not work but the hazard lights do. The turn lever is also very hard to maneuver. Where should I start?
Click to expand...
I had the same issue except for the stiff turn lever. mine was on my MGB the flasher unit was bad. everything worked perfectly after replacing the unit. it was a quick fix. But as the other responders here have advised a car sitting that long should have the wiring gone over top to bottom...and yes especially the grounds. rodents love to eat wiring. and depending on where this car was stored they may have had a field day. be safe and not sorry. bad wiring can be a fire waiting to happen. good luck. btw a little electrical lube spray may ease the joint of your turn lever
 
My lever fell apart when I tried to move it - had to get a replacement from Moss which seems to work just fine. I had the added trickery of dealing with installing 1970 equipment into a 1973 body/harness, so the ground connection for the in-lever horn button didn't exist in my wiring harness.

If you buy a new one, make sure you get the right one unless you're doing something foolish like me....
 
For my ‘77 B, when the turn signals and hazard lights were not working, it turned out that the hazard switch on the dash was bad. On my ‘77, the turn signal flasher and the hazard flasher are both wired to the back of the dash hazard switch. Because the switch was bad, neither was working. Replacing the switch on the dash worked for me. It’s probably best to check grounds and other connections first, but a new switch is pretty inexpensive.

Al
‘77 MGB
Brooklands Green
 
I had better luck taking the switch apart and cleaning it. The replacement switch I bought had an issue with the spade connectors on either side of the switch. They would pull out of the switch when I attempted to remove either wire. (dash lights)
 
I should probably have done the same. Aftermarket parts are almost always not as good as original. Luckily, the new switch that I purchased worked well.
 
I had a hazard switch from Moss fall apart the first time I tried to connect the wires to it - fortunately they were real good about getting me a no-cost replacement since it was only a few weeks old. My original 40+ year old one disintegrated in my hands - the plastic was just so brittle.
 
I have not had a ton of luck (IE No luck) repairing the old hazard switch and had to buy a new one, but, in this case we have many easier options to try before we get to the hazard switch (I hope)
 
I just got the turn signals up and running. A new flasher and cleaning the points on the turn lever solved the problem. Unfourtenetly the hazard lights don't work so that will be the next fix.
 
Sometimes the hazards don't work because a bit of corrosion builds up on the contacts over time since the switch is so seldom used. If you're lucky turning the switch on and off a number of times will clear that and they'll work.
 
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