I have a spare EAS unit, and last weekend i did a refurb of the block and the compressor. I know that the driver pack cannot be repaired as such, but is there a way to bench test it ?

Yes. With the driver pack connected to the valve block, go to the connector that would connect to the outside world (C152). See the following diagram but bear in mind this is the loom side and not the plug side so it is mirror image.

Easy enough to follow as the two pins for ground (10 and 11) re black and the two for power (12 and 13) are red. Put power and ground onto those two pairs (a standard spade terminal will go over both pins) and then you can apply power to the pin for the each valve. If you hear the valve go click, it is working, if it doesn't, that channel is dead.

Tnx Richard