U1420-IMPLAUSIBLE ELECTRONIC GEAR SELECT SIGNAL RECEIVED

For a complete wiring diagram, refer to the Wiring Information.

When Monitored:
TCM supply voltage is between 10 and 16 volts.

Ignition switch Run position signal is detected via dedicated circuit to TCM.

Engine speed (CAN message) is greater than or equal to 550 rpm.

The above conditions are met for 5 seconds.

There are no ignition switch failures.

There are no CAN bus or CAN message failures between the TCM and BCM.

Monitored continuously once the conditions are met.
Set Condition:
The TIPM reports via CAN message that the electronic gear select signal is not available.

Possible Causes
TOTALLY INTEGRATED POWER MODULE (TIPM) CAN BUS DTCS
TIPM DTCS
TRANSMISSION CONTROL MODULE (TCM)

1. VERIFY THE DTC IS ACTIVE

1.	Turn the ignition on.

2.	With the scan tool, record and erase the DTCs.

3.	Cycle the ignition switch from off to on.

4.	With the scan tool, read the DTCs.

Is the DTC active at this time?

Yes

2. CHECK IF TOTALLY INTEGRATED POWER INVERTER MODULE (TIPM) CAN BUS DTCS ARE PRESENT

1.	With the scan tool, read the TIPM DTCs.

Are there any TIPM CAN BUS DTCs present?

Yes

3. CHECK IF TIPM DTCS ARE PRESENT

1.	With the scan tool, read TIPM DTCs.

Are there any TIPM DTCs present?

Yes

Using the schematics as a guide, check the Transmission Control Module (TCM) pins, terminals, and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace the TCM in accordance with the Service Information.
Perform the TRANSMISSION VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) /Standard Procedure).

4. INTERMITTENT WIRING AND CONNECTORS

1.	Using the wiring diagram/schematic as a guide, inspect the wiring harness and connectors.

2.	Wiggle test the wiring harness and connectors while monitoring the scan tool data relative to this circuit.

3.	Look for the data to change or for the DTC to reset during the wiggle test.

4.	While monitoring the scan tool data relative to this circuit, move the selector switch to each position several times.

5.	Look for the data to change other than as expected or for the DTC to reset.

Were any problems found?

Yes

Test complete, the condition or conditions that originally set this DTC are not present at this time.