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 disable the SRS system.

   NOTE:

   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 E29 certification ECU (smart key ECU) connector.
   Fig 1: Identifying E29 Certification ECU (Smart Key ECU) 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
   E29-27 (CANH) - E29-28 (CANL)	Engine switch off	54 to 69 Ω

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Certification ECU)

NG → REPAIR OR REPLACE CERTIFICATION ECU (SMART KEY ECU) BRANCH WIRE OR CONNECTOR (CANH, CANL) 

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 E29 certification ECU (smart key ECU) connector.
   Fig 2: Identifying E29 Certification ECU (Smart Key ECU) 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
   E29-17 (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
   E29-1 (+B) - Body ground	Always	11 to 14 V
   E29-19 (ACC) - Body ground	Engine switch on (ACC)	11 to 14 V
   E29-18 (IG) - Body ground	Engine switch on (IG)	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Certification ECU)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   4