Entry Interior Alarm does not Sound: Procedure

WARNING: This page is about a different car, the 2011 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.

CHECK COMBINATION METER ASSEMBLY (OPERATION)
1. When the engine switch is on (IG) and the shift lever is in R, check that the combination meter buzzer sounds.
  OK
  
  Combination meter buzzer sounds.
NG → See step 2

OK → See step 3
GO TO METER / GAUGE SYSTEM (Proceed to Problem Symptoms Table). Refer to PROBLEM SYMPTOMS TABLE
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to REMOVAL