Reverse Light not working - Bulb and Circuit Good

[Mr Rover]

Howdy folks,

Simple Sunday morning job - change a blown reverse light.
Much to my surprise, the bulb turns out to be fully functional!

So I get out the test light to check the circuit at the plug. Test light shows all good - until you insert a globe into the socket, then nothing.

I tried plugging a different functional lamp assembly into the plug (I grabbed an indicator) and that didn't work either.

Finally, I checked the earth, that was all good.

What should I look for next and / or should I order a replacement plug?

https://www.aulro.com/afvb/images/imported/2015/07/207.jpg

[sierrafery]

Hi, take a voltmeter and make somehow to insert the probes in the plug from behind while it's plugged to the cluster(if you can't insert thin needles thrugh the insulation of the wires as to contact the core and measure on those), as you described the syndrome you should get 12V without the bulb inserted, insert the bulb and see if the voltage drops or not.... if no drop and still no light the problem is in the plug-cluster-bulb link somewhere... if it drops low it means there's a bad contact somewehere, measure with negative probe on body then to see if the voltage drops this way too or not...if yes there's bad earth despite of your initial check, if the voltage drops against body too, it's bad contact on the feed circuit... do these tests and report back then we'll speak again

[towe0609]

See PM - just offering to help if it turns out its a problem with the plug (pictured)

[DEFENDERZOOK]

where did you test for earth........?

at the wire....or the globe holder itself.....?