Hello, I have a crank no start condition and suspecting the cps. When I try to start it there is no rpm reading on the tach or my scanner. Fuel pressure climbs to about 18000 kpa and then slowly goes down after I stop. I installed a lift pump last summer and timing belt/water pump over the winter with 0 problems since then. The day it quit was a hot one. Is there anything else I can try to diagnose this? It looks like if I move the coolant overflow out of the way I can maybe get to the cps?

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Short of having an oscilloscope to test the CPS signal and if you did not get any DTC's when using a scanner, no.
The CPS are known for going bad and not producing a signal as they go through the heat up cycle of the engine.
Some have put a ohm meter on the signal pins and put the CPS in a pot of water and heat the water on a stove and monitor the signal to see if it looses continuity as it goes thought a heat up cycle.
They don't always set a DTC when they go bad either, so you cannot depend on that as a true indicator.

When mine was going bad back many years ago, it put me on the side of the road twice and never set any DTCs. I had to set there until it cooled off and allowed the engine to restart.

Best to just replace it, and it is much easier to access it from underneath the vehicle if you can get on a lift or drive up ramps.
If you have to jack it up, be SURE and use jack stands and do it safely. See picture 2 below.

Autozone can provide you with the OEM Bosch CPS in their "reboxed" Duralast line; that is where I purchased mine about 10 years ago.

Duralast Crankshaft Position Sensor Part #SU8492

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Supporting Vendor and Moderator of LOST
05 Jeep Liberty CRD Limited
Ironman Springs/Bilstein/Shocks
Yeti StgIV Hot Tune
Week's BatteryTray
No FCV/EGR
Samcos/ProVent
SunCoast/Transgo
Carter Intank-pmp
2mic.Sec.Fuel Filter
Flowmaster/NO CAT
V6Airbox/noVH
GM11 Bld.fan/HDClutch
IronrockArms/wwdieselMount
98 Dodge Cummins 24 Valve

Thank you. Do you know how many volts the sensor puts out? I downloaded a phone oscilloscope app that works with a raspberry pi, but it only works up to 3.3 volts. It did not generate a wave when I tested either sensor, I don't know how set the parameters yet, but the old sensor was putting out around 0.8 volts and the new one was around 2.2 volts when I waved metal at them. The jeep does start now with the new sensor, I just want to make sure before I button everything up.

Sent from my SM-A326U1 using Tapatalk

According to the FSM, the CPS is just a two wire magnetic pickup positioned close to a toothed reluctor wheel on the crankshaft.
The FSM does not show the voltage used by the FSM across the sensor.
Some sensors use 5v reference voltage provided by the ECM.

_________________
Supporting Vendor and Moderator of LOST
05 Jeep Liberty CRD Limited
Ironman Springs/Bilstein/Shocks
Yeti StgIV Hot Tune
Week's BatteryTray
No FCV/EGR
Samcos/ProVent
SunCoast/Transgo
Carter Intank-pmp
2mic.Sec.Fuel Filter
Flowmaster/NO CAT
V6Airbox/noVH
GM11 Bld.fan/HDClutch
IronrockArms/wwdieselMount
98 Dodge Cummins 24 Valve

I don't know if you already found the problem, but just to document it here, my other CRD threw a P0725 and P0700 last month. No other symptoms. I had replaced the crank sensor 10 years ago after the engine started randomly quitting when hot, with no codes. That solved it until now. Replaced it again with the Duralast part, cleared the codes and all has been well for a month or so.

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05CRD: GDE Hot ECU & TCM tunes, Provent, Cat filter, Facet lift pump, TransGo kit, Florida TC, Samcos, stainless brake lines, HDS thermostat, Renegade light bar,
RL super sliders, Bilstein adjustables, Al's Gen 4.5 Arms, 235/85-16 Duratracs, DTT rear, Elocker front, EVIC+TPMS, Turbo timer, McNally pillar gauges, Weeks Stage II kit.