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MG MGB Technical - Turn signal issue

Hello everyone,
My 1971 mgb roadster GHN5UB237466G has a turn signal issue. When signalling a left turn, everything works perfectly.
When signalling a right turn nothing works. The lights don't light up. The dash green arrow indicator doesn't light, and the flasher doesn't pulse.
The 4 way emergency lights also quite. Again no lights, the inside red flashing light doesn't flash, and no sound from the flasher. I don't routinely check the 4 way lights having never had occasion to use them, so it might not have happened at the same time but it seams suspicious.

So far: I have removed, bought new, and tested both filaments in the front and rear bulbs. Both are fine. In fact every bulb in the car works - dash lights, courtesy light, trunk light, side markers, parking and head lights. Everything except the right side turning lights.

The car is fresh out of winter storage so there may have been a mouse issue though no evidence of that.
Anybody had something similar
G Nicholas

If the hazard flashers aren't working at all i.e. either side it's probably a separate issue. That has it's own fuse - brown wires both sides - don't know where that would be on a North American. Likewise the hazard flasher, which should have a brown wire on one side. If you can find it check for 12v on the wire.

With nothing working on the right-hand side it's either all three bulbs failed which would be unusual for the dash bulb, or the switch contacts are not closing that side, have a look at the switch.

paulh4

Common problem if the hazards haven't been used for ages, and you've only had the issue since you tried them ----give the hazard switch a bit of a workout turning it on-off several times to hopefully clean up the contacts inside and all will return to normal

willy
William Revit

That only worked short-term for me, eventually I opened up the switch (easy enough with the earlier rockers, dug out all the old hardened grease that was acting as an insulator and put fresh in, been fine for getting on 30 years now ... mind you, only used twice a year :o)
paulh4

Thank you for your comments.
Since my first post, the left side has gone intermittent. Trying to think of a common point for failure for left and right I came up with the flasher or the switch. I started poking around with my continuity light and found all the fuses are fine, there is power to the flasher even though the turn signal stalk is in the off position. That surprised me. I thought the power would go through the turn signal switch to the flasher but it looks like it goes the other way.

While testing, the right side indicators worked exactly once! I swapped in a new flasher which didn't work either. So I think it is a switch issue, so I am off to the local LBC shop for some expert help. I'll post again when the results are in.
Glen
G Nicholas

The power has to go to the flasher unit first otherwise you would need one for each side of the car after the indicator switch. The hazard flasher is the same.

If both sides consistently either work or don't work at the same times then it is likely to be in the common area i.e. 12v supply through the hazard switch and flasher unit and switch. If the sides do different things at different times then more likely the output side of the switch through to the corners of the car.
paulh4

Issues solved. The emergency lights came back just by cycling the switch on/off many many times. Started working, and now works every time. I'll have to make a point of turning them on every so often.
The turn signal issue required the steering wheel removal where it was discovered the green brown wire tip was barely making contact. It was trimmed up and re-soldered. Everything is now good. Also tightened up the fuse box connections.

Weird symptoms with a happy ending. Thanks everyone for your suggestions. Glen
G Nicholas

This thread was discussed between 01/05/2023 and 08/05/2023

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