Champion Pub right boxer arm not working. Everything else on the pin is working fine.

I know that the wiring is all good. I know that the coil is good. Both the left and right (low power) solenoids are driven by pin number J133-3. The left arm works fine, so I assume that means that J133-3 is good. Right arm drive Xistor is Q43 and playfield drive connection is J113-4. Drive wire color is BRN-ORG

PLEASE can someone tell me how to test the transisitor or anything else I should be testing?

I bought a low end digital meter but have no idea where the probes should go or what setting the dial should be on. Do I test with power on or off?

I would be VERY grateful for your help.

Thanks - Roger