[Marcos]

A 95 4.0L would have a separate TCM to control the transmission functions. I believe the same key trick will work to pull codes, but you have to watch the blinking of the OD light. There might also be a trick involved, like holding the OD button while you turn the key on and off. The TCM codes are different from the PCM codes.

Several electrical things could keep the OD from engaging. The OD solenoid could have a short or open, or the transmission fluid could be reading too hot due to a bad temp sensor.

 

[Marcos]

1993-1995 4.0l Grand Cherokees (ZJ) had a TCM for the 42RE. In 96 control was incorporated into the PCM. Also, on this design the transmission temp sensor is either attached to the solenoids, or build into the governor pressure sensor transducer (if it has 4 wires. if it has 3, it's separate)