Any update. Your issue is similar. I'm going to go back through the posts and the diagrams now. I have a very similar issue with my 97, 4.0, 5 speed manual.
Starter won't turn over when ignition is turned to start. Resistance on the starter relay (pins 85 and 86) checks good with 78 ohms. I have 12 volts on pin 30 on the relay. I have 12 volts on pin 85 when ignition is turned to start. The clutch safety switch has been jumpered. I can jump the terminals on the starter solenoid with a screwdriver and the Jeep will start and run fine. Looking on manual page 8w-21-4. It appears the powertrain control module controls the ground through s134. I'm thinking the computer does not want to let it start. I had forgotten about the ASD relay but still thinking it's just that the PCM isn't happy and isn't going to ground the starter relay when it shold to start.
Have you checked the (3) 32 pin harness connectors that snap into the ECU receptacles ?
Check for grey oxidation on the ECU receptacle pins and wiring harness clips.
This would hinder the grounding that you are missing.
Just because the starter relay coil reads 78 ohms doesn't mean it is good; as load is applied the coil resistance can increase which stop the relay from closing.
Use another known "good" relay and swap it out as a test.
