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
t, read the engine DTC’s. Check and repair all engine DTC’s prior
to performing transmission symptom diagnostics.
With the DRBIII
t, 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 P0705 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 flash level of 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.
45RFE AUTO
TRANS
Continue
Go To
2
2
With the DRBIII
t, check for other transmission DTC’s
Are there any line pressure related DTC’s P1720, P1721, P1722, P1724, or P1791
present?
45RFE AUTO
TRANS
Yes
→
Refer to symptom list and perform test for Loss of Prime or Line
Pressure DTC’s.
Perform 45RFE TRANSMISSION VERIFICATION TEST - VER
1.
No
→
Go To
3
3
With the DRBIII
t, check for other transmission DTC’s
Is a DTC P0734 and/or P1733 present also?
45RFE AUTO
TRANS
Yes
→
Replace the Transmission Solenoid/TRS assembly in accordance
with the Service Information.
Perform 45RFE TRANSMISSION VERIFICATION TEST - VER
1.
No
→
Go To
4
4
Start engine.
Warm transmission to 180 degrees.
CAUTION: Firmly apply brakes.
While monitoring transmission line pressure with the DRBIII
t, move the shift lever
to each gear position and record the line pressure reading.
Allow the pressure to stabilize for at least 5 seconds in each range.
Did the line pressure remain at a steady value between 85 and 95 PSI during the
procedure?
45RFE AUTO
TRANS
Yes
→
Go To
5
No
→
Go To
11
115
TRANSMISSION
P1727-4C HYDRAULIC PRESSURE TEST FAILURE —
Continued