Pinpoint Test Ah: DTC U0140 - Lost Communication With Body Control Module (Gem)

WARNING: This page is about a different car, the 2007 Lincoln MKX and 2007 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.

AH1 RETRIEVE THE RECORDED DTCs FROM BOTH THE CONTINUOUS AND ON-DEMAND INSTRUMENT CLUSTER SELF-TESTS
- Check for recorded instrument cluster DTCs from the continuous and on-demand self-tests.
- Is DTC B1318 recorded?
1. YES : Go to Pinpoint Test AD .
2. NO : Go to AH2.
AH2 RECHECK THE INSTRUMENT CLUSTER DTCs
- Repeat the instrument cluster self-test.
- Clear the DTCs.
- Is DTC U0140 still present?
1. YES : Go to AH3.
2. NO : The system is operating correctly at this time. The DTC may have been set due to an intermittent communication drop off from high network traffic.
AH3 RETRIEVE THE RECORDED DTCs FROM BOTH THE CONTINUOUS AND ON-DEMAND AUDIO UNIT SELF-TESTS
- Check for recorded audio unit DTCs from the continuous and on-demand self-tests.
- Is DTC U0140 recorded?
1. YES : REFER to MODULE COMMUNICATIONS NETWORK article to diagnose no communication with the SJB.
2. NO : Go to AH4.
AH4 CHECK THE NETWORK OPERATION
- Carry out the network test.
- Does the SJB pass the network test?
1. YES : Go to AH5.
2. NO : REFER to MODULE COMMUNICATIONS NETWORK article to diagnose no communication with the SJB.
AH5 CHECK FOR CORRECT SJB MODULE OPERATION
- Disconnect all the SJB connectors.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect all the SJB connectors and make sure they seat correctly.
- Operate the system and verify that the concern is still present.
- Is the concern still present?
1. YES : INSTALL a new SJB. REFER to MULTIFUNCTION ELECTRONIC MODULES . TEST the system for normal operation.
2. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.