Disconnecting the sensor arm and raising it to mimic a low rear end for 17-27 seconds should invoke the pump to start. Lowering the arm for same time should cause a relief of pressure to lower car.

If the pump doesn't run for that initial 2-5 second burst after the key it ON for 35-55 seconds...
Check the fuse 5B in IP fuse block. 10 A. It provides power for ABS and CCR also if you have that. That circuit resets the Automatic Level Control Sensor to start the timing for the 35-55 second relief and pump up.

Other power comes through RH Maxifuse A5 30 Amp, but if you can run the pump from the inflator timer relay, that power has to be working. The Inflator uses the relay on passenger side junction block, so your relay is okay.

On the Automatic Level Control Sensor--with the arm attached--with the key ON you should have 12 volts positive on C which is RED. You should also have 12 volts on D which is BRN and is the ignition circuit that turns on with the ignitions. The C Red is hot all the time.

Lead A on the sensor should be ground.

Testing the sensor by bypassing it: calling for pump due to low vehicle height should cause Wire B Yellow to be grounded inside the sensor--it is hot with the same voltage a D through the relay in the passenger compartment. So using a fused!!! wire to ground B to a good ground should turn on the pump. If so, your sensor may be bad.

I troubleshot my ELS on my 98 from the front to the back when it quit working. I should have started at the rear instead. Got all the way to the back and I found a wire in the bundle that comes through the trunk floor grommet behind the rear wheel was broken inside due to continual flexing in the air stream behind the rear wheel. Outside of the plastic looked okay, but the copper was open.

The monkey wrench is that if you don't have 12 volt positive to line C Red, that might be because the Inflator timer relay is not switching the power back to that circuit when it shuts off. The power for that line goes into the Inflator relay on D RED and out on B Red when the timer is not calling for the pump to run. When the Inflation timer operates that line is switched.

Good luck.

No it doesn't run. I guess I'm going to have to figure out how to check the switch or bypass it to see if it will run the pump.
I tried this and it still doesn't start the pump.
.I also checked the 5 b fuse and it was not blown.
I'll have to check the wiring since as you say the pump will operate via the on switch in the trunk and there is enough pressure generated to fill a tire.