what is the question sure all the above. how to DIY a very complex trans, (super complex)\ it is no 4R60E , easy send on GM products. oops, last line says how to search for the problem. well this is common vast cars and truck this failure. howto best search means how to diagnose a failing transmission, (get the service manual on it,would be first. this box is complex 7 solenoids or so. , 5 speed box + oD + TTC LOCKE. ZF5HP19 causes: 1: external PCM/TCM error, or wiring from tcm to box bad, damaged. 2: bad solenoid TCC in the box. 3: bad TC the TCC locker inside TC is bad. the shop manual told all that. lacking the real manual ZF one can google the parts and they do have names, the connector as pins and all SOL can be Ohmed out, PAN ON . Measure ohms first, to all SOL. they are not using ISO names (ASE OR SAE) names for soleniods MV, EDS, TOT, OSS, TSS. so one must dig deep to learn those. OK TOT is box temp, sure. OK ss = speed sensors output and turban(input to box) so which one MV or EDS is it of the nifty 7 PAN OFF ANDSince one of the 5HP19 solenoids is located on the top of the valve body, it also has to be removed. CC is normally called EDS4 in this diagram it's call EDSWK. free manuals here
https://at-manuals.com/manuals/zf-5hp19/ google finds this all in seconds.
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