Took some photos of two GEMS ECMs. Maybe someone will find them interesting. ECM on the left is from an AEL 97. ECM on the right is from a 99. There are some obvious differences and many subtle differences. Most of the ICs actually have different part numbers between the two years.

 

Few of the ICs have actual part numbers on them. The have date codes and Land Rover stock numbers.
The micros would have different numbers dues to different programming internally.

 

And perhaps Lucas stock numbers. In competitve early production and prototype circuit boards not uncommon to find all the numbers wiped off with solvent to add extra steps to reverse engineering.

You can note that many components use surface mount technology, so hobbyist repair is limited. And one can imagine why a slug of sea water from the beach would have a bad impact on an un-sealed ECU for those that frolic in the surf.

 

You're correct, I meant to say Lucas, not LR.

I bought an ECU/TPU combination off of Ebay, the ECU besides having corrosion on the housing, had a good quantity of sand in it.

 

What you don't see is a clear sealant spray on the board for high humidity applications. Wonder if that is something we could add?

 

It seems to be there on the one I disassembled.