Coolant Temperature gauge inoperative. 05 xc90 2.5L Turbo

United States
What I Drive
2005 xc90 2.5L Turbo
Hi, I am new to your site and I am hoping someone can tell me the location of splice #53-319. This is in the engine compartment and is part of the temperature gauge circuit. I purchased a wiring diagram for the 2005 xc90, however it does not include splice locations. I have a engine code for the coolant sensor (CTS) I replaced the sensor and drove the car 15 minutes and the gauge dropped to cold. Removed the connector and installed a 300 ohm resistor, checked the gauge and it stayed at cold. CEL on, I checked codes and cleared code. Gauge went to mid position. took car for a road test (with resistor still installed, drove approximately 1/2 hour when I pulled back into driveway temp gauge dropped back to cold. Disconnect battery and removed ECM to inspect connections, all appear OK. Assembled removed components and drove to work the next morning .After driving 1/2 hour the CEL came on, returned home from work that evening
and found that I now have 2 codes, one for the CTS nd one for the IAT. Checked the wiring diagram and found they share splice #53-319. Could someone please provide a location of this splice so I don't cut open the complete engine harness.

Thanks for your time,
Rod Kirkpatrick