I'm assuming that this is the Sol 06 lock magnet; if not, the transistor and fuse numbers may be incorrect, but the testing procedures are still valid.

I'm uncertain what this coil should measure, but I would have to say 5.3 ohms (as seen on your meter) is likely normal; if in doubt, you can compare it to your ramp magnet as they should measure the same. Make these measurements at the playfield connector, just to make sure they are good at that point.

I would also verify you aren't blowing F103.

If you don't find any issues there, just flip over your ribbon cable between the CPU and PDB so that you are using different contacts on the cable. If this fixes it you need a new cable.

If it's still not working put both your meter leads into the playfield connector that normally goes to the magnet; with the game powered on, you should measure 0V with the magnet off and 50V when the magnet is turned on. If this doesn't happen, Q66 is likely bad; a secondary cause would be failure of its driver Q62.

You perform this test directly on the connector with the magnet disconnected, what you are checking is that there is a difference in potential across the magnet in order for current to flow. If there is none, no current can flow through the circuit and the magnet cannot energize; when there is a difference, its measurable and would allow for the magnet to energize. Since the magnet doesn't work, this test should fail, and put you on the right path to correcting the problem. If you are 100% sure the board is working properly, than this only leaves the connectors and wiring to the magnet.

J133-2 to one side of the magnet connector, and J116-7 to the other side; you can also perform a resistance check to these points with the power off if its preferable or easier.
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