Diagnostic Procedure

WARNING: This page is about a different car, the 2005 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.

DIAGNOSTIC TEST REFERENCE - P0944-LOSS OF PRIME

TEST	ACTION	APPLICABILITY
1	NOTE: Low fluid level can be the cause of many transmission problems. If the fluid level is low locate and repair the leak then check and adjust the fluid level per the Service Information. NOTE: Always perform diagnostics with a fully charged battery to avoid false symptoms. With the DRBIII®, read the engine DTC's. Check and repair all engine DTC's prior to performing transmission symptom diagnostics.With the DRBIII®, read Transmission DTC's. Record all DTC's and 1 Trip Failures. NOTE: Diagnose 1 Trip Failures as a fully matured DTC. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.Repair as necessary.Perform the Shift Lever Position Test. If the test does not pass, refer to Symptom test for P0706 CHECK SHIFTER SIGNAL .For Gear Ratio DTC's, check and record all CVI's.Most DTC's set on start up but some must be set by driving the vehicle such that all diagnostic monitors have run. NOTE: Verify the flash level of the transmission controller. Some problems are corrected by software upgrades to the transmission controller. NOTE: Check for applicable TSB's related to the problem. Perform this procedure prior to Symptom diagnosis.ContinueGo To 2	All
2	Start the engine. The transmission must be at operating temperature prior to checking pressure. A cold transmission will give higher readings. Firmly apply the brakes and place the gear selector in reverse. With the DRBIII®, monitor the Transmission Line Pressure. Is the Line Pressure below 1034 kPa (150 PSI) or is it fluctuating more than +/- 69 kPa (10 PSI). No --> Go To 3 Yes --> Go To 4	All
3	The conditions necessary to set this DTC are not present at this time. Verify with the customer if a delayed engagement and/or an intermittent "No Drive" condition has occurred. If the customers answer is "No" erase the DTC and return the vehicle to the customer. Make sure to check for any TSBs or controller flash updates that my apply. With the DRBIII®, check the EATX DTC EVENT DATA to help identify the conditions in which the DTC was set. Has the customer experienced any delayed engagement and/or "No Drive" conditions? Yes --> Repair internal transmission problem as necessary. Replace the Transmission Oil Pump if inspection reveals no signs of internal seal leakage. Refer to the Service Information for the proper repair procedure. Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1 . No --> Test Complete.	All
4	Using the DRBIII®, perform a Shift Lever Position Test. Follow the instructions on the DRBIII®. Did the Shift Lever Position Test pass? Yes --> Go To 5 No --> Refer to the TRANSMISSION CATEGORY and perform the appropriate symptom. Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1 .	All
5	Remove and inspect the Transmission Oil Pan per the Service Information. Remove and inspect the Primary Oil Filter per the Service Information. Inspect the oil filter O-ring for damage and proper installation. Does the Oil Pan contain excessive debris and/or is the Oil Filter plugged or O-ring damaged? Yes --> Repair the cause of the plugged transmission oil filter or excessive debris, Seal installed onto filter neck instead of into pump bore, seal not fully seated against pump housing, filter neck not engaged into pump. See Service Information. Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1 . No --> Go To 6	All
6	If there are no possible causes remaining, view repair. Repair Repair or replace the Transmission Oil Pump as necessary. Refer to the Service Information for the proper repair procedure. Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1 .	All