1977 XJ S2. Original turn signal flasher unit died. The Lucas replacement is currently unavailable so I got the DAC 1731. No schematic and the lugs are numbered differently. So I took a guess and hooked it up in the same order as the original. Turn the key, and it starts cycling on its own without touching the stalk, and neither signals or indicators light up? Any suggestions?

 

that does not look like a flasher, it does look like a relay.
do you still have the old flasher ? Post a photo of it.

 

That round device is it. I think. Any turn signal flasher of that vintage I’ve ever seen was a round canister.

 

I can be wrong.

 

see below

 

I think a flasher is different.

In my 1984 XJ-6, the flasher is a Hella TBB44. It also has the following number and markings on it:
4DB003425-03
2(4) x 21W+0...5W12V
Made in Germany
A 71373 DOT

The terminals are marked 31 49a 49 C
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You’re right and I’d delete this post if I could.
Boy did I screw the pooch on this one but fortunately I didn’t cause further damage.
Still don’t have turn signals but do have emergency flashers so it must be the stalk.
I shall go Woodshed myself

 

well we all mess up every now and then.
if no turn signals, replacing the stalk switch means first removing the steering wheel. Try to get the factory service manual and follow the steps to the letter.
The switch can be rebuilt, I have done a few. I think I have a rebuilt Series 2 switch.

 

Thanks for the offer. I have a used spare of unknown condition from a ‘76 model, but as it happens, after thoroughly spraying the unit with contact cleaner and working it in without seeing any results, after sitting for a couple of hours the stalk works again like nothing ever happened.
Sheesh

 

Grease is the word...