Pinpoint Test As : U0140
- NOTE: The Inverter System Controller (ISC) is referred to as the SOBDMC (Secondary On-Board Diagnostic Control Module C) in the scan tool.
Normal Operation and Fault Conditions
REFER to: Electric Powertrain Control - System Operation and Component Description .
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition SOBDMC U0140:00 Lost Communication With Body Control Module: No Sub Type Information This DTC sets when messages are missing from the BCM. Possible Sources
- Communications network concern
- BCM
- AS1 VERIFY THE CONCERN
- Ignition ON.
- Verify there is an observable symptom present.
Is an observable symptom present?
Yes GO to AS2 No CLEAR the DTC. The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition. - AS2 VERIFY THE DIAGNOSTIC SCAN TOOL COMMUNICATES WITH THE BCM (BODY CONTROL MODULE)
- Connect the diagnostic scan tool to the vehicle.
- Attempt to establish a vehicle session using the diagnostic scan tool.
Can a vehicle session be established?
Yes GO to AS3 No REFER to: Communications Network . - AS3 CHECK FOR NON-NETWORK DIAGNOSTIC TROUBLE CODES (DTCS)
- Using a diagnostic scan tool, carry out the Inverter System Controller (ISC) self-test.
Are any non-network DTCs present?
Yes DIAGNOSE all non-network DTCs first. REFER to Diagnostic Trouble Code (DTC) Chart . No GO to AS4 - AS4 CHECK FOR NON-NETWORK BCM (BODY CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
- Using a diagnostic scan tool, carry out the BCM self-test.
Are any non-network DTCs present?
Yes REFER to Diagnosis and Testing in the appropriate Multifunction Electronic Modules article. No GO to AS5 - AS5 CHECK THE INVERTER SYSTEM CONTROLLER (ISC) AND BCM (BODY CONTROL MODULE) CALIBRATION LEVELS
- Verify the Inverter System Controller (ISC) and the BCM are at the latest calibration levels.
Are the Inverter System Controller (ISC) and the BCM at the latest calibration levels?
Yes GO to AS6 No UPDATE the Inverter System Controller (ISC) or BCM to the latest calibration level. - AS6 RECHECK FOR DTC (DIAGNOSTIC TROUBLE CODE) U0140
- Using a diagnostic scan tool, clear the Inverter System Controller (ISC) DTCs.
- Ignition OFF.
- Ignition ON.
- Wait 10 seconds.
- Using a diagnostic scan tool, carry out the self-test for the Inverter System Controller (ISC).
Is DTC U0140 present?
Yes GO to AS7 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. - AS7 CHECK FOR OTHER CAUSES OF NETWORK COMMUNICATION CONCERNNOTE: If new modules were installed prior to the DTC being set, the module configuration can be incorrectly set during the PMI or the PMI may not have been carried out.
- Check the vehicle service history for recent service actions related to the BCM and the Inverter System Controller (ISC). If recent service history is found:
- verify correct replacement module was installed
- vehicle parts build list may be used to verify correct part fitment
- verify the configuration of replacement module was correct
- re-configure module using as-built data if prior configuration is suspect
- verify the module was not obtained from a like vehicle and installed into vehicle with concern
- return the swapped module to source vehicle and obtain new replacement module
- verify correct replacement module was installed
- Operate the system and determine if the observable symptom is still present.
Is the observable symptom still present?
Yes GO to AS8 No The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration. - Check the vehicle service history for recent service actions related to the BCM and the Inverter System Controller (ISC). If recent service history is found:
- AS8 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION
- Ignition OFF.
- Disconnect and inspect the BCM connectors.
- Repair:
- corrosion (install new connectors or terminals - clean module pins)
- damaged or bent pins - install new terminals pins
- pushed-out pins - install new pins as necessary
- Reconnect the BCM connectors. Make sure they seat and latch correctly.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, REFER to: Communications Network . No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.