Pinpoint Test N: DTC U0140

Power Liftgate

Pinpoint Test N: DTC U0140

Normal Operation

- DTC U0140 (Lost Communication With Body Control Module (GEM))- an on demand DTC that sets when the Liftgate/Trunk Module (LTM) does not receive data messages received from the Body Control Module (BCM) over the Medium Speed Controller Area Network (MS-CAN) for 5 seconds or longer. For a complete list of all network messages, refer to Information Bus.

This pinpoint test is intended to diagnose the following:

- BCM (Body Control Module)

- LTM (Liftgate/Trunk Module)

PINPOINT TEST N : DTC U0140

N1 VERIFY THE CUSTOMER CONCERN

- Ignition ON.

- Verify there is an observable symptom present.

Is an observable symptom present?

Yes
GO to N2.

No
The system is operating normally at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

N2 CHECK THE COMMUNICATION NETWORK

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: Network Test.

- Carry out the network test.

Does the Body Control Module (BCM) pass the network test?

Yes
GO to N3.

No
REFER to Information Bus.

N3 RETRIEVE THE RECORDED DTCs FROM THE BCM (Body Control Module) SELF-TEST

- Check for recorded DTCs from the BCM (Body Control Module) self-test.

Is DTC U3003:16 or DTC U3003:17 recorded?

Yes
REFER to Body Control Systems.

No
GO to N4.

N4 RETRIEVE THE RECORDED DTCs FROM THE LTM (Liftgate/Trunk Module) SELF-TEST

- Check for recorded DTCs from the Liftgate/Trunk Module (LTM) self-test.

Is DTC B1317 or DTC B1318 recorded?

Yes
For DTC B1317, GO to Pinpoint Test L Pinpoint Test L: DTC B1317.

For DTC B1318, GO to Pinpoint Test M Pinpoint Test M: DTC B1318.

No
GO to N5.

N5 RECHECK THE LTM (Liftgate/Trunk Module) DTCs

- Clear the DTCs.

- Wait 10 seconds.

- Repeat the LTM (Liftgate/Trunk Module) self-test.

Is DTC U0140 still present?

Yes
GO to N6.

No
The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

N6 CHECK FOR DTC U0140 SET IN OTHER MODULES

- Clear all DTCs.

- Ignition OFF.

- Ignition ON.

- Wait 10 seconds.

- Enter the following diagnostic mode on the scan tool: Self-Test.

- Retrieve the continuous memory DTCs from all modules.

Is DTC U0140 set in the Driver Seat Module (DSM) or the Instrument Panel Cluster (IPC)?

Yes
INSTALL a new BCM (Body Control Module). CLEAR the DTCs. REPEAT the self-test.

No
INSTALL a new LTM (Liftgate/Trunk Module). REFER to Liftgate/Trunk Module (LTM) . TEST the system for normal operation.