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MGB Unknown connector on alternator

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TheRealDestrux

TheRealDestrux

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Hello, I replaced my alternator on my 1977 MGB, it’s making about 15.2 volts to the battery (a little high) and I’ve been having some issues, my high beams aren’t working, my reverse lights sometimes work and sometimes don’t, my wipers stopped working, and blinkers also sometimes work or not. This happens with the car running and also not running. I didn’t have this issue before. (Besides the blinkers)

However I did find this connector connected to the alternator harness and don’t know if this is important and possibly creating my issue on my 1977 MGB, it’s not plugged in and I haven’t found the other end yet.

Thank you.
 

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Short update: The lights and wipers are fixed, the bullet connectors behind the dash are loose in their connector and I will replace them.

Still want to find out what that connector goes to though.
 
what colour are the wires leading to the connector?
 
So, not sure exactly which is which but it seems to be connected to the Opus Ignition / CEI ignition - and possibly the ignition amplifier. This MG's attempts at electricronic ignition with mixed results.

One of these links - should be relevant.

mgexp.com/forum/mgb-and-gt-forum.1/distributor-coil-amplifier-wiring-question.891592/


 
Those colors are all associated with the ignition circuit, but I don't remember seeing that type connector before. And if the car starts and runs, I'm not sure it's needed; but also not sure why it's there. Hopefully, someone with more knowledge will chime in (Doc, you readin'?). In the meantime, if you don't already have it, here's a link to color-coded wiring diagrams for all MGB models; scroll down to the '77 for yours.

Keep us posted on your findings.

:cheers:
Mickey
 
Those colors are all associated with the ignition circuit, but I don't remember seeing that type connector before. And if the car starts and runs, I'm not sure it's needed; but also not sure why it's there. Hopefully, someone with more knowledge will chime in (Doc, you readin'?). In the meantime, if you don't already have it, here's a link to color-coded wiring diagrams for all MGB models; scroll down to the '77 for yours.

Keep us posted on your findings.

:cheers:
Mickey
Now that you mention it, my alternator was bad and the ignition light never came on, nor has it ever come on. So this connector probably shows me when I have an issue such as that. However I do not know where it connects.
 
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