DTC U0327: Software Incompatibility with Vehicle Security Control Module: Procedure

1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.
   WARNING:

   Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.

   NOTE:

   • After the power switch is turned OFF, the HDD navigation system requires approximately 6 minutes to record various types of memory and settings. As a result, after turning the power switch OFF, wait 6 minutes or more before disconnecting the cable from the negative (-) battery terminal.
   • When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION .

NEXT: Go to next step 

1. Disconnect the L15 certification ECU connector.
   Fig 1: Identifying L15 Certification ECU Harness Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Switch Condition	Specified Condition
   L15-27 (CANP) - L15-28 (CANN)	Power switch OFF	54 to 69 Ω

NG → REPAIR OR REPLACE CERTIFICATION ECU BRANCH WIRE OR CONNECTOR (CANP, CANN) 

OK: Go to next step 

1. Connect the cable to the negative (-) battery terminal.
   NOTE:

   When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION .

2. Disconnect the L15 certification ECU connector.
   Fig 2: Identifying L15 Certification ECU Harness Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   L15-17 (E) - Body ground	Always	Below 1 Ω

4. Measure the voltage according to the value(s) in the table below.

   Standard voltage

   Tester Connection	Switch Condition	Specified Condition
   L15-1 (+B1) - Body ground	Always	11 to 14 V
   L15-20 (CUTB) - Body ground	Always	11 to 14 V
   L15-18 (IG) - Body ground	Power switch ON (IG)	11 to 14 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   4