P128E
P128E - Transmission Power Control Circuit 2 Overcurrent
For a complete wiring diagram, refer to.
• When Monitored: Ignition ON with battery voltage greater than 10.0 volts.
• Set Condition: The totally integrated power module has detected an overcurrent condition in the transmission control output circuit.
Test Step 1 - Determine if the DTC is Active
• Ignition ON, engine not running.
• With a scan tool, read TIPM DTCs.
Is the DTC Active?
Yes
• Go to Test Step 2.
No
• Go to Test Step 6.
Test Step 2 - Test the Transmission Control Output Circuit for a Short to Ground
• Turn the ignition switch to the LOCK position.
• Remove the transmission control relay from the TIPM.
• Due to different power control configurations, the transmission control relay may be referred to as a PCM relay.
• Disconnect the transmission solenoid/TRS assembly harness connector.
• Disconnect the PCM C4 harness connector and connect Miller tool #8815.
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 perform diagnosis.
• Measure the resistance between ground and the transmission control output circuit.
Is the resistance less than 10k ohms?
Yes
• Repair the circuit for a short to ground.
• Perform Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test
No
• Go to Test Step 3.
Test Step 3 - Test the Transmission Control Output Circuit
• Connect the PCM harness connector.
• Connect the transmission solenoid/TRS assembly harness connector.
• Connect the positive probe of an ammeter to battery positive and connect the negative probe to the transmission control output circuit in the relay connector in the TIPM.
• Read the amperage on the ammeter.
Is the amperage less than 1.0 amp?
Yes
• Go to Test Step 5.
No
• Go to Test Step 4.
Test Step 4 - Test the Powertrain Control Module
• Disconnect the ammeter from battery positive.
• Disconnect the PCM harness connector and connect Miller tool #8815.
• Connect the positive probe of an ammeter to battery positive.
• Read the amperage on the ammeter.
Is the amperage less than 2.0 amps?
Yes
• Using the schematics as a guide, check the PCM terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace and program the PCM. Refer to With the scan tool, perform Quick Learn.
• Perform Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test
No
• Go to Test Step 5.
Test Step 5 - Test the Transmission Solenoids
• Disconnect the ammeter from battery positive.
• Disconnect the PCM harness connector and connect Miller tool #8815.
• Connect the positive probe of the ammeter to battery positive.
• Monitor the amperage on the ammeter in the following step.
• Using a jumper wire, momentarily jump each solenoid control circuit to ground one at a time in the appropriate terminals of Miller tool #8815.
• Use the chart to compare the ammeter readings.
Are the amperages within limits?
Yes
• Using the schematics as a guide, check the TIPM terminals for corrosion, damage, water intrusion, or terminal push out. Check for any service bulletins that may apply. If no problems are found, replace and program the TIPM.
• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior
No
• Depending on the identified solenoid, replace the transmission solenoid/TRS assembly.
• Perform the Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test
Test Step 6 - Intermittent Wiring and Connectors
• The conditions necessary to set the DTC are not present at this time.
• Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
• Wiggle the wires while testing for short and open circuits.
• With the scan tool, check the DTC event data to help identify the conditions in which the DTC was set.
Were there any problems found?
Yes
• Repair as necessary.
• Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior
No
• Test complete.