I’m sorry, I assumed you were having intermittent MLT problems. Are you saying the car won’t run up at all? Do you have a set of prints? With the meter on AC, before trying to run, read from AC1 to AC2, you’ll read 120 vac, now read from AC1 to TSL3. If you still have 120 vac you have verified the TSL3/TSL4 Contact is good (you will also have TSL input high.) now clip one lead on TSL3 and give the car an up call. You should read 120 vac at MS1 since the pump is running. Now read MS2, if you lose voltage here check the aux contact on Delta. Now read voltage at UTS1, if you lose voltage here, it could be FST, DN2, or UP1 Relay contacts. If you do have UTS1, UTS input will be high, now check voltage at TSL2, if you lose voltage here, the problem is in the switch tree, UTS or TSL switch or wiring. If you do have 120 vac from TSL2 to TSL3 then you should have 120 vac from UFS1 to UFS2 and the up fast coil should be picked. If your problem is in the switch tree, pull the CS6 MTA plug from the selector and clip your leads from pin 11 to 15, put the meter on audible continuity, pull the tree up on the car and open up the UTS and TSL switches.