I will check for a large load short. It does look like a small short as it will sometimes throw a spark, then stops completely after reconnecting the negative battery cable. The relay frame has ground continuity and so does the firewall its attached to. After a few days of testing, I found the fuel relay is good on 87 (fuel pump +), 85 (fuel pump -), and 30 (red fusible link); its 86 that is the culprit, which I believe the ECU activates the ground to open the circuit. The line to the fuel pump is good. I believe the fuel pump is dead.
So as only the headlights, instrument panel, and starter works; I suspect a ground short is effecting the ECU, unless the ECU is dead. I am working cleaning all grounds and C101 connector (cruiser54 specs) with no changes yet. I am hesitating on putting in the new pump in case there is a large load short, as something finished the electric fuel pump; it was working a year ago when the car would not start and then died.
I did notice that five wires around the O2 exhaust area have no sheathing and look dark. I will take your advice below from a thread I reviewed and thanks!
"Do not power it up as you now must find the short. Place the black meter lead on black battery lead, and the red meter lead in the Pin 87 socket, disconnect the plug to the fuel pump module, if there is a short, it will read low resistance 2-3 Ohms. If it reads OL or infinity. Place the meter in the tone or buzzer position and wiggle the cable. Obvious places are where the cable crosses the exhaust pipe or is routed around bends."
I did give up looking for a fuel pump ballast resistor on this 87 XJ Renix (no fifth ballast pin on the starter relay either) and now consider the fuel pump relay 30 pin to red fusible link, the only fuse in the circuit. Battery cable and second cable are the main grounds to the engine block, which is where I believe the ECU is grounded. I have never confirmed where the fuel pump is grounded; that one cable may handle that too.
93 XJ 4.0L S6 Auto 190000 LLANO SPORT
87 XJ 4.0L S6 Auto 244000 DESERT RAT