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MG MGB Technical - bad flasher on one side only?

I jsut purchased my first B, a '73. I do have some work to do before inspection and one of the items I thought would be easy included the flashers.
I get a flash on the left side but a solid on the right. The flasher is obviously working and power is going to all lights. Could a new flasher be the answer or is this one of those Lucas mysteries that this board warned me about before this purchase? Will any two pole flasher substitute>
John K

Check the bulbs on the right side.

One of them is either burned out (most likely), or the wiring connectors is not making solid contact.

Check the ground (black) wires for that circuit, too.
Daniel Wong

On the side that does not flash, change the bulb.
Dan

John. I have had problems with the US flasher units. Problems went away when I switched to a Lucas unit. But, as the others have said, it sounds like a bulb or a contact problem. Clean out the bulb holders with a round wire brush and clean the bulbs themselves to ensure good contact. Les
Les Bengtson

If one bulb glows and the other doesn't change the one that doesn't glow. If both bulbs glow you could have one or more incorrectly rated bulbs, or a bad connection on that side. The most likely position for this is where the lighting units connect to the body (there are no ground wires, it just relies on the mechanical fixings), but it could also be in athe holders themselves or any of the connectors back to the turn switch. Careful voltage measurements between the sides might help locate it.
Paul Hunt

John,
I had the same problem and it was caused by a rotted connector where the blinker wire joins then main harness , under the fuse box. Replaced the connector and all was well.

graeme
graeme collings

I also am a new owner. From past experience with other vehicles it can be a very touchy thing to get the blinker to 'read' the lights correctly... can you get into the relay connections to check the impedence to grown through each light? They should all be the same - and the lights should be the same rating (watts).

I have a similar concern - the left signal blinks correctly (every second or so) but the right blinks very slowly (every 5-6 seconds) and it won't automatically turn off on the side. Two problems?

I'm out to look for that relay box myself now. G'luck John and let me (us) know how you turn out.
Craig Hahn

Problem resolved! Cleaned out the right front fixture and all flashers work fine. Good advice from this board. Next are the low beams that died when the flashers were corrected.
thanks for the help
john

Craig - two problems, one electrical one mechanical.

The slow side could be caused by an incorrect bulb or a bad connection on that side. Check the bulb ratings and measure the voltages through the circuits comparing good side to bad as advised before.

For the non-cancelling remove the column cowl and watch happens with the cancelling fingers on the switch and post or cam on the column.

John - if the main beams work from the dipswitch as well as the headlamp flasher then power is reaching the switch at least. Check the continuity of the blue/red from the switch to the bullet connectors at the front. You have possibly disturbed the 4-way connector on the RHS.
Paul Hunt

Headlamp mainbeam problem has been identified as the solid blue connection located just behind the slip ring. This connection looks really corroded and will require some surgery that will need to wait until Sat. Anyway fiddling with this connection gets the main beams back in order.
I've been into this car for a week and have already learned to read the wiring diagrams. Wife already hates the car and it hasn't even made it out of the garage yet.
JohnK

This thread was discussed between 30/01/2002 and 01/02/2002

MG MGB Technical index

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