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Codes 743, 753 Where to start?

I am a little confused when looking at the transonline write up. It shows a test of the solenoid resistance with neg. probe in D7 (ground) with pos. probe in the solenoid circuits which are c14,15,16. Is that the correct way to do test the solenoid circuits?

I am getting no readings at all.
 
moz-screenshot.png
AW4_99_Connector.jpg
 
OK, just tested 11,12,13 and all at 13.3 about. So the solenoids and circuits are good at their current state.
 
Well, if it runs ok when you shift gears by hand, (tcm disco'ed) and doesn't shift properly when you have the TCM connected and let the TCM do the shifting, I would suspect that the TCM is bad.
Are you still getting the 743 and 753 codes when everything is connected and you just put it in Drive and let the TCM do the shifting?
 
McQue said:
Well, if it runs ok when you shift gears by hand, (tcm disco'ed) and doesn't shift properly when you have the TCM connected and let the TCM do the shifting, I would suspect that the TCM is bad.
Are you still getting the 743 and 753 codes when everything is connected and you just put it in Drive and let the TCM do the shifting?
Click to expand...

Correct, codes come on after 5 min of driving even when it's running fine.
The thing that makes me think it could be something other than the TCM, is when I've unplugged it, b/c it wouldn't downshift, the jeep still runs poorly, sputtering backfiring and stalling.

Could the TPS go haywire when hot but be fine otherwise?
 
Changed the TPS with an aftermarket piece, Seems like it runs a little worse so I'm putting the old one back in. Any one have a good TCM I could borrow?
 
TCM installed. I think I reset the MIL by grounding the pos battery cable, ignition on,lights on,off ignition off. Started it up and light was off. Let it warm up and now the MIL is back on. I guess my next step is to change the solenoids. Junk yard here I come.
 
I don't have a obd-2 reader so I don't know what codes are showing. Is it posable that the TCM needs to be re-flashed for my vin?
 
TCM doesn't need to be reflashed.
You need to verify the codes.
You must be chasing more than 1 problem.
I wouldn't replace the solenoids until you fix the "sputtering, backfiring and stalling" problem.
Something going on here when it warms up and you put the engine under load.
Can you verify fuel pressure?
 
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