DTC B2772: Control Module Communication Stuck

DTC DETECTING CONDITION: 

when all the following conditions are met.

• battery voltage stays at 10 v or more for longer than one second.
• can bus is not in sleep state.
• clear memory is not in process.
• can message register freezes in the tpms & keyless entry control module or the keyless entry control module

TROUBLE SYMPTOM: 

• communication is impossible with subaru select monitor.
• can not be locked/unlocked with keyless entry system.

1. CHECK DTC  .
   1. turn the ignition switch to off.
   2. disconnect the tpms & keyless entry control module connector or keyless entry control module connector.
   3. connect the disconnected connectors.
   4. using the subaru select monitor, perform the clear memory of [keyless entry]. ref. to common (diag)>clear memory .

      clear memory 

   5. turn the ignition switch to off.
   6. turn the ignition switch to on.
   7. read the dtc of [keyless entry] using the subaru select monitor. ref. to keyless entry (diagnostics)>diagnostic trouble code (dtc) .

      dtc check 

   is dtc b2772 displayed? (current malfunction)

   yes:  replace the tpms & keyless entry control module or keyless entry control module. ref. to security and locks>keyless entry control module .

   even if dtc is displayed, the circuit has returned to a normal condition at this time. reproduce the failure, and then perform the diagnosis again.

   NOTE: in this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.