Electronic Control Unit (ECU) harness compatibility

[T.Hanson]

Just curious before learn by doing. I have harness's and ECU's, collected from '79-'81 5, 6ers. The one in question has broken injector connectors. Easier to swap in a spare harness than replace the connectors.

What are the predictions the (necessary) pins will connect between the ECU and spare harness ?

[PatinaBeforePolish]

Looks like the e12 up to 79 is different than an 80/81 but I'm sure they could be made to work. Some components like the jules verne device are located in different places so maybe just a question of length (?). I have no experience with a thermal reactor car. E24's look similar but I believe there're extra connections in the harness.

Why not just replace the connecters? They're out there as kits on Amazon, ebay or from the dealer and include the plastic connecter plus 2 pins per pack. The rubber covers are available as well. A proper ratcheting crimping tool makes the job very easy. And you may be surprised how many of the original connectors are loose.

[T.Hanson]

Thank you for the future alternatives.

[Mike W.]

79 used a different ECU than 80-81 but they're fully interchangeable. IIRC the difference is there is a different trigger when it transitions from open loop to closed loop in the warm up phase. 79 E24s however are different, both harness and ECU, they didn't go to an O2 sensor until 80, unlike E12s which started in '79.

But I agree with Patina, IMO it would be much easier to swap connectors than the whole harness. I've found the 2 pin injectors easy to swap out, but no luck on the 3+ terminal ones.