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MG TD TF 1500 - Lucas SD84 indicator switch

Have I bought a "duff" switch? I've studied numerous diagrams in order to try and solve my problem. On the switch a Lucas SD84 fitting it to my TC there are 6 terminals numbers. Numbers 3 and 4 have permanent continuity and which I believe are the power in from the flasher unit. However no matter which way the switch is operated there is no continuity between 3/4 and any other terminal which I believe should allow power to flow via terminals 2 or 5 dependant on which indicator is required. There is a very low resistance permanently between terminals 1 and 6. I would also note that although some wiring diagrams show fitted brass links between terminals 1 and 2 and 6 and 5 there are none on my unit. Besides stamped SD84 there is also a number on a plate on the handle 31476D. Can anyone advise please?
JK Mazgaj

,
There is a wiring diagram on the Holden website under "Technica Advice".
https://www.holden.co.uk/p/manual_indicator_switch_black_lever

Regards
Declan
Declan Burns

Hi Declan, Thank you.That is one of the many diagrams I have studied. I still believe that there must be either links missing or a faulty switch as apart from as stated continuity between terminals 3 and 4 there is no continuity between the power in terminal (the one with the brass strip to the light bulb terminal) or any other terminal no matter what position the switch is in. Surely when either to the left or to the right continuity should occur between power in terminal and either terminal 2 or 5?
JK Mazgaj

Jan, Autochron website has a handy rear view picture. John.
J P Hall

Thanks John. Have seen that image- and many others. But still seek confirmation as to whether there are any internal contacts or additional link wiring to provide continuity. Logically as no matter what position the switch and I get no terminal allowing current to the lights as supplied from the flasher unit to terminal 3 I have faulty switch. However before taking the matter up with the supplier I wanted confirmation that I'm not missing something.
JK Mazgaj

Problem solved. Studying the various pictures on line I realised that the orientation of the switch handle on the switch purchased was 180 degrees opposite. Turning the backing plate gently to amend this provided me with the continuity required.
JK Mazgaj

This thread was discussed between 09/03/2023 and 10/03/2023

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