Trane XE1200 air handler blower not coming on

Hey whats up guys,

Im having issues at home.

It all started 2 weeks ago when the house got warm and I went to the inside unit and noticed that the low pressure line going into the unit was frosted and I could not hear the blower.

It was the middle of the night so I just shut the breaker off and let it melt. In the morning I checked it and verified the blower was not coming on. I did go outside and the outside unit was working.

I research a bit online about the issue and found somewhere that it said to cehck for 24vac at R & G and I did and it said to jump the two to see if the motor came on and I did and it started fine. Well after this the blower started to work with no issues for about 4 days.

After 4 days I noticed that the blower fan was coming on for a few seconds and then turning off for a few seconds and then coming back on and it kept doing. This happened again during the night so I left it for the morning. When I got up I went and checked the outside unit and the fan was not running and did noticed that the fan spun freely but not nice and smooth. I checked the capacitors and the start capacitor was bad so I went and grabbed a new one and installed it but the fan did not start until I helped it with a stick. After it started I went upstairs and the air handler blower was still turning on and off and on and off but it was throwing out cool air. The next day I went outside and the fan was not on again and it would not start even if I helped, troubleshot it to a bad motor and ordered one online and got it in yesterday.
I installed it this morning and had my wife turn on the breaker inside the house while I was outside and the outside fan works like a charm. The issue is that when i went upstairs I went to the air handler and the blower is not working now. I tried jumping R & G again but now its not doing anything. I checked the control board and its good and and check for voltage in the 5 pin plug that goes into the ECM and there is voltage there.

Any ideas what this could be?

Some still-unknown root cause that is making things fail.

If you replace any more parts, monitor the voltage and current to them for a while.
Things that last only four days must be seeing some severe abuse; overvoltages, high resistance connections, intermittent connections, etc..

meter the voltage to the blower motor and see what your voltage is when the motor drops out. This will tell you if the motor is shutting down based on voltage or thermal overload in which case, you have bad blower capacitor or blower motor.

When looks like the blower is no longer coming on. I got a zebra vz7 tester and eliminated the thermostat and the control board and motor. The only thing is that I have a ecm 2.5 and I a video that said the zebra variable universal tester doesn't work with the 2.5. I was ready to order an ecm but after reading that now I don't know what do to.

Any ideas?

This job is above your ability. Probably mine, too. . .

OK so I figured out that I need the ECM.

My module is about $365.00 and thats the least expensive I have found.

I have found a few used motor/ecm combo for sale that have the same specs 3/4hp 220v and would like to know if I can go ahead and buy one of these combo deals and replace both as a set?

If yes do I have to do anything special with the current dip switches?

Thanks,
Darwin

Your approach to troubleshooting is creating a sinkhole for money and for labor.

You may have already fallen into this
http://www.google.com/search?client=safari&rls=en&q=sunk+cost&ie=UTF-8&oe=UTF-8
trap.