Responding to all
The key fob locks and unlocks the vehicle so that system is good.
The shift leaver is back communicating to the instrument cluster. I unplugged c207 and reconnected and the display came back???? and stayed communicating.
In terms of the RCM being good, I replaced the fuel pump relay with one I purchased from NeedsWings.
I have watched the RCM as wife was performing attempted start and the fuel pump relay pulled in for fraction of second so believe PCM has control over it.
Manually activated fuel pump relay and listened to it run so circuit looks good.
Traction control relay output drives shift leaver mod and as the instrument cluster displays shifter position that circuit is verified.
Engine control relay output from RCM is on pin E5 and is 12 volts. To verify checked voltage on O2 sensor and its good.
Yes I'm confident RCM is good. Even the Horn works
Regarding Fan control module, the center wire RD/PK has 12 volts when Key "on".
I have been disconnecting the battery when I'm finished for the day, so every day when reconnected I try to start. Nothing has changed. Get no start attempt, just lights on instrument cluster as previously stated.
I started the thread on the Data link connector because the manual has placed a high value on the SCI condition as an indicator of Module health and thought it may be helpful to others doing troubleshooting.
If you deem inappropriate please relocate/delete as you think in the best interest of the form. You will not offend me in any way.
Now as far as the instrument cluster displaying the shifter position, do we know for sure that communication goes through the Transmission mod and not directly from shifter to instrument cluster?
Looking for a way to verify the Transmission control module is good to eliminate it and move on. According to the module troubleshooting section of the service manual, I measure 0 volts at the Data link connector, which according to the manual indicates a bad module, but reading and performing the steps listed ( I don't have a DRB ll tool) I believe it is misleading. I connected the plug C1 to the module when measuring voltage.
My 1968 Mustang is so much easier to work on, but this is progress.
Thanks everyone contributing.