It's probably a bad ground or dirty or loose battery cable. Check that both cables are clean, tight, not corroded with in the insulation and that all the far ends have clean tight connections. Both hot and ground. There are 5 or 6 ends to check.
Or replace BCM, PCM, or Instrument cluster.
What GM says about it:
U1096 DTC U1096: LOSS OF COMMUNICATION WITH IPC (NO SOH MESSAGE RECEIVED)
Description: Serial data circuit is used to communicate information between systems. Each system in serial data line is assigned to its own recognition code (address). This code is used to identify which module or systems are communicating. Systems periodically send State Of Health (SOH) message to each other. DTC U1096 will set and store in RFA (Remote Function Actuation) system if RFA system sends out SOH message to Instrument Panel Cluster (IPC), and no SOH message response was sent back. This condition must be present for 5 seconds. No driver warning message will be displayed for this DTC. Under all fault conditions, DTC U1096 requires an ignition cycle from LOCK/OFF to RUN position before the DTC will clear. If conditions for malfunction no longer exist, history DTC will clear after 50 consecutive ignition cycles. DTC U1064 will also clear when conditions no longer exist, using IPC clearing DTCs feature or when scan tool is used to clear codes. Testing 1. If referenced to this test from REMOTE KEYLESS ENTRY DIAGNOSTIC SYSTEM CHECK, go to next step. If not referenced to this test from REMOTE KEYLESS ENTRY DIAGNOSTIC SYSTEM CHECK, go to REMOTE KEYLESS ENTRY DIAGNOSTIC SYSTEM CHECK under SYSTEM TESTS. 2. Turn ignition off. Install a scan tool to Data Link Connector (DLC). DLC is located under driver's side of dashboard. Turn ignition on. Using scan tool, attempt to communicate with Instrument Panel Cluster (IPC). If communication with IPC is successful, go to next step. If communication with IPC is not successful, go to BCM DIAGNOSTIC SYSTEM CHECK under SYSTEM TESTS. 3. Using scan tool, read RFA DTCs. If DTC U1255 is set, go to DTC U1255. If DTC U1255 is not set, go to next step. 4. Using scan tool, read Body Control Module (BCM) DTCs. If DTC U1096 is set, go to BODY CONTROL MODULES - CORVETTE article. If DTC U1096 is not set, go to next step. 5. Inspect serial data line for an intermittent open, short to ground or short to voltage between RFA system and IPC. Inspect splice pack 206 (instrument panel harness serial data line). Make sure bus bar is properly inserted. Inspect harness connectors for loose or damaged terminals. If a problem was found and repaired, go to step 8 . If a problem was not found, go to next step. 6. Turn ignition off. Ensure all components and connectors are connected and installed properly. Turn ignition on. Clear DTCs. See CLEARING CODES . Using scan tool, read RFA DTCs. If DTC U1096 is set, go to next step. If DTC U1096 is not set, system is okay. 7. Replace remote control door lock receiver. See REMOTE CONTROL DOOR LOCK RECEIVER under REMOVAL & INSTALLATION. Program both transmitters. See TRANSMITTER PROGRAMMING & SYNCHRONIZATION under SYSTEM PROGRAMMING. Program all Tire Pressure Monitor (TPM) sensors. See TIRE PRESSURE MONITOR (TPM) SENSOR PROGRAMMING under SYSTEM PROGRAMMING. Go to next step. 8. Turn ignition off. Ensure all components and connectors are connected and installed properly. Turn ignition on. Clear DTCs. See CLEARING CODES . Go to REMOTE KEYLESS ENTRY 1Search™ 2/2 DIAGNOSTIC SYSTEM CHECK under SYSTEM TESTS. Diagnostic Aids If problem is an intermittent loss of communications, carefully inspect serial data line and related components for following intermittent conditions: Intermittent open, short to ground or voltage in serial data line. Intermittent loss of communication with IPC. Damaged or loose star connector terminals. If serial data line is shorted to ground or voltage, all systems connected to same serial data line will not be able to communicate properly. If DTC U1096 is stored in RFA system, check for same DTC stored in Body Control Module (BCM). BCM also monitors SOH message from IPC. If BCM has DTC U1096 stored, check IPC for intermittent malfunction. If BCM does not have DTC U1096 stored, check for open in serial data line between RFA system and IPC. RFA system must also be checked for intermittent operation due to a loss of power or ground. After repair, clear DTC from all systems capable of storing this DTC.
