Page 2865 of 5267

2.INTERMITTENT OPERATION
The conditions necessary to set this DTC are not present at this time.
Test drive the vehicle. Allow the Transmission to shift through all gears and ranges.
Was a delayed engagement and/or a no drive condition present during the testdrive?
Ye s>>
Go To 4
No>>
Go To 3
3.INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specifictothiscircuit.
Wiggle the wiring while checking for shorted and open circuits.
With the scan tool, check the EVENT DATAto help identify the conditions in which the DTC was set.
Were there any problems found?
Ye s>>
Repair as necessary.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Te s t C o m p l e t e .
4.SHIFT LEVER POSITION TEST
With the scan tool, perform a Shift Lever Position test. Follow the instructions on the screen.
Did the Shift Lever Position Test pass?
Ye s>>
Go To 5
No>>
Perform the diagnostic procedure for P0706-CHECK SHIFTER SIGNAL.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
5.CHECK FOR PLUGGED TRANSMISSION FILTER
Remove the Transmission Pan and inspect the Transmission Fluid and Transmission Filter per the Service Informa-
tion.
Does the Transmission Oil Pan contain excessive debris and/or is the Oil Filter plugged?
Ye s>>
Repair the cause of the plugged Transmission Filter. Refer to the Service Information for the proper
repair procedure.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Replace the Transmission Oil Pump per the Service Information.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
Page 2866 of 5267

P0992-2/4/OD HYDRAULIC PRESSURE TEST
For a complete wiring diagramRefer to Section 8W.
When Monitored:
In any forward gear with engine speed above 1000 RPM, shortly after a shift and every minute thereafter.
Set Condition:
After a shift into a forward gear, with engine speed greater than 1000 RPM, the PCM momentarily turns on
element pressure to the clutch circuits that do not have pressure to identify that the correct pressure switch
closes. If the pressure switch does not close 2 times the DTC sets.
Possible Causes
CONDITION P0992 PRESENT
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 42RLE - DIAGNOSIS AND TESTING).
Theory of Operation
Pressure switches are normally off or open (no pressure applied) and read high (+12 volts). When an element is
applied, the corresponding pressure switch closes to ground (0 volts) or turns on. The controller tests the OD and
2/4 pressure switches when they are off (when the corresponding friction element is not applied) by briefly applying
the OD and 2/4 elements which will cause the corresponding pressure switchto close. The test verifies that the
switches are operational and that the switch will close when the corresponding element is applied. If a switch fails
to respond, it is re-tested. The MIL illuminates and the transmission system defaults to Limp-in mode.
1.CHECK TO SEE IF DTC P0992 IS CURRENT
NOTE: The vehicle must be driven to set this DTC. The transmission must at operating temperature with the
Engine RPM above 1000 RPM.
This DTC is an indication of both the 2/4 and the O/D Hydraulic Pressure Switch DTCs present.
Perform the diagnostic procedures for both P0845 and P0870.
With the scan tool, check the DTC EVENT DATA to help identify the conditionsin which the DTC was set.
If there are no possible causes remaining, view repair.
Repair
Refer to the Transmission category and perform the diagnostic proceduresfor P0845 and P0870.
Page 2867 of 5267
P128B-TCM POWER CONTROL CIRCUIT 2 LOW - TIPM
For a complete wiring diagramRefer to Section 8W.
Page 2868 of 5267

When Monitored:
With the ignition on. Battery voltage greater than 10 volts.
Set Condition:
A shorted condition is detected in the Transmission Control Output circuit.
Possible Causes
(T16) TRANSMISSION CONTROL OUTPUT CIRCUIT SHORT TO GROUND
(T16) TRANSMISSION CONTROL OUTPUT CIRCUIT FOR AN OPEN
TOTALLY INTEGRATED POWER MODULE (TIPM)
Diagnostic Test
1.CHECK IF THE DTC IS ACTIVE
Ignition on, engine not running.
With the scan tool, check TIPM DTCs.
Is the status Active for this DTC?
Ye s>>
Go to 2
No>>
Go to 5
2.CHECK THE (T16) TRANSMISSION CONTROL OUTPUT CIRCUIT SHORT TO GROUND
Turn the ignition off
Disconnect the TIPM C10 harness connector.
Disconnect the PCM C4 harness connector and install Miller tool #8815.
CAUTION: Do not probe the PCM harness connectors. Probing the
PCM harness connectors will damage the PCM terminals resulting
in poor terminal to pin connection. Install Miller tool #8815 to per-
form diagnosis.
Measure the resistance between ground and the (T16) Transmission
Control Output circuit.
Is the resistance below 5.0 ohms?
Ye s>>
Repair the (T16) Transmission Control Output circuit for a
short to ground.
Perform 42RLE TRANSMISSION VERIFICATION TEST -
VER 1. (Refer to 21 - TRANSMISSION/TRANSAXLE/AU-
TOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Go to 3
Page 2869 of 5267

3.CHECK THE (T16) TRANSMISSION CONTROL OUTPUT CIRCUIT FOR AN OPEN
Turn the ignition off to the lock position.
Connect the TIPM C10 harness connector.
Disconnect the Transmission Solenoid/Pressure Switch harness connec-
tor.
Disconnect the Line Pressure Sensor/Variable Force Solenoid harness
connector (if equipped).
Ignition on, engine not running.
Using the scan tool under the TIPM Actuators, actuate the Transmis-
sion.
Using a 12-volt test light connected to ground, check the (T16) Trans-
mission Control Output circuits.
NOTE: The test light must illuminate brightly. Compare the bright-
ness to that of a direct connection to the battery.
Does the test light illuminate brightly at all the (T16) Transmis-
sion Control Output circuits?
Ye s>>
Go To 4
No>>
Repair the (T16) Transmission Control Output circuit for an
open.
Perform 42RLE TRANSMISSION VERIFICATION TEST -
VER 1. (Refer to 21 - TRANSMISSION/TRANSAXLE/AU-
TOMATIC - 42RLE - STANDARD PROCEDURE)
4.TOTALLY INTEGRATED POWER MODULE
Using the schematics as a guide, inspect the wire harness and connectors.
Check the TIPM harness connector terminals for corrosion, damage, or terminal push out.
Pay particular attention to all power and ground circuits.
Were any problems found?
Ye s>>
Repair as necessary.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Replace the Totally Integrated Power Module per Service Information.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
5.INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
While monitoring the scan tool data relative to this circuit, wiggle test the wiring and connectors.
Look for the data to change or for the DTC to reset during the wiggle test.
Were any problems found?
Ye s>>
Repair as necessary.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Te s t c o m p l e t e .
Page 2870 of 5267
P128C-TCM POWER CONTROL CIRCUIT 2 HIGH - TIPM
For a complete wiring diagramRefer to Section 8W.
Page 2871 of 5267
When Monitored:
With the ignition on. Battery voltage greater than 10 volts.
Set Condition:
A shorted condition is detected in the TIPM TCM Power control circuit.
Possible Causes
(T16) TRANSMISSION CONTROL OUTPUT CIRCUIT SHORT TO VOLTAGE
TOTALLY INTEGRATED POWER MODULE (TIPM)
Diagnostic Test
1.CHECK IF THE DTC IS ACTIVE
Ignition on, engine not running.
With the scan tool, read TIPM DTCs.
Is the status Active for this DTC?
Ye s>>
Go to 2
No>>
Go to 4
2.(T16) TRANSMISSION CONTROL OUTPUT CIRCUIT SHORT TO VOLTAGE
Turn the ignition off
Disconnect the TIPM C10 harness connector.
Disconnect the PCM C4 harness connector.
Measure the voltage of the (T16) Transmission Control Output circuit.
Is the voltage above 10.0 v?
Ye s>>
Repair the (T16) Transmission Control Output circuit for a
short to voltage.
Perform 42RLE TRANSMISSION VERIFICATION TEST -
VER 1. (Refer to 21 - TRANSMISSION/TRANSAXLE/AU-
TOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Go to 3
Page 2872 of 5267

3.TOTALLY INTEGRATED POWER MODULE
Using the schematics as a guide, inspect the wire harness and connectors.
Check the TIPM harness connector terminals for corrosion, damage, or terminal push out
Pay particular attention to all power and ground circuits.
Were any problems found?
Ye s>>
Repair as necessary.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Replace the Totally Integrated Power Module per Service Information.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
4.INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
While monitoring the scan tool data relative to this circuit, wiggle test the wiring and connectors.
Look for the data to change or for the DTC to reset during the wiggle test.
Were any problems found?
Ye s>>
Repair as necessary.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 42RLE - STANDARD PROCEDURE)
No>>
Te s t c o m p l e t e .