Circuit Description
WARNING: This page is about a different car, the 2004 Lexus ES 330. However, it is still accessible from the selected car via links, so may be relevant.
DTC B1214 and B1215 will be output when +B and body ground is short-circuited on the communication bus. Detecting this condition will make all the BEAN communication unable and output some DTC.
HINT:
Theft warning ECU (theft deterrent ECU) has a single communication line. Therefore, if the line becomes short (bus-down), the BEAN communication will not be impossible and DTCs will not be output multiply, either.