I have the code P1745 which is the line pressure solenoid 1 and its not due to the weak battery the battery has been changed as well as a new alternator and the battery is charging well. I tried searching online for a diagram to see which solenoid on the valve body it is but no luck. If anyone has any remedies please let me know being stuck in 4th gear isn't great.

 

Sonnax 5hp24 solenoid identification

There is picture and interal codes for the solenoids.
Below is the more human names starting from right to left. EDS1 is #1 below:

#1 Pressure regulator 1
#2 Pressure regulator 4
#3 Pressure regulator 3
#4 Pressure regulator 2
#5 Pressure regulator 5
#6 Solenoid valve 1
#7 Solenoid valve 2
#8 Solenoid valve 3

 

I started getting faults for pressure regulators/solenoids in my 2000 XJ8L.

First it was #2, cleared the DTCs and then another different one. (#5?)

I got tired of the random regulator/solenoid faults so I went to my faulty gearbox pile and took the row of solenoids and the internal harness out of a broken one.(bad forward drum and SCREACHING noise)

Installed the used solenoids (all 8) and the harness into the 2000 XJ8L and no more issues.