Fiat based Citroens need a S.1279 adapter to talk to some ECU’s with Lexia/Diagbox.
Pins 4 & 5 are both earths, in some setups only one of them may be connected & sometimes they are connected together, it may be normal on this for pin 4 or 5 to be un connected. More likely you just need the adapter.
Lexia 9780.z5
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