Pinpoint Test AX: DTC U0140

Seats

Pinpoint Test AX: DTC U0140

Refer to Wiring Diagram Set 14, Module Communications Network for schematic and connector information. [1][2]Diagrams By Number

Normal Operation

The Driver Seat Module (DSM) and the Smart Junction Box (SJB) communicate using the Medium Speed Controller Area Network (MS-CAN). Messages are exchanged between the modules on the MS-CAN (Medium Speed Controller Area Network) for the purposes of determining what functions are being carried out.

- DTC U0140 (Lost Communication With Body Control Module (GEM))- set by the DSM (Driver Seat Module) whenever it has lost communication to the SJB (Smart Junction Box) for 15 seconds or longer as long as the module voltage is between 10 and 15 volts.

This pinpoint test is intended to diagnose the following:

- Module communication

- DSM (Driver Seat Module)

- SJB (Smart Junction Box)

PINPOINT TEST AX : DTC U0140

AX1 VERIFY CUSTOMER CONCERN

- Ignition ON.

- Verify there is an observable symptom present.

Is an observable symptom present?

Yes
GO to AX2.

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.

AX2 CHECK THE COMMUNICATION NETWORK

- Ignition ON.

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

- Carry out the network test.

Does the SJB (Smart Junction Box) pass the network test?

Yes
GO to AX3.

No
REFER to Information Bus.

AX3 RETRIEVE THE RECORDED DTCs FROM THE SELF-TEST

- Check for recorded DSM (Driver Seat Module) DTCs from the self-test.

Is DTC B1317 or DTC B1318 recorded?

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

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

No
GO to AX4.

AX4 RECHECK THE DSM (Driver Seat Module) DTCs

NOTE: If new modules were installed prior to the DTC being set, the module configuration may be incorrectly set during Programmable Module Installation (PMI) or the PMI (Programmable Module Installation) may not have been carried out.

- Clear the DTCs. Repeat the DSM (Driver Seat Module) self-test.

Is DTC U0140 still present?

Yes
GO to AX5.

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.

AX5 CHECK FOR DTC U0140/U0140:00 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/U0140:00 set in other modules?

Yes
INSTALL a new SJB (Smart Junction Box).

No
INSTALL a new DSM (Driver Seat Module). REFER to Driver Seat Module (DSM) .