DTC B2274: ACC Monitor Malfunction (07/2015 -): Procedure

See step  1

Result:  NG

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR IN CIRCUIT CONNECTED TO POWER SOURCE 

Result:  OK

OK 

See step  2

See step  2

Result:  NG

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result:  OK

OK 

See step  3

1. Disconnect the H56 certification ECU (smart key ECU assembly) connector.
2. Disconnect the 3B instrument panel junction block assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   H56-4 (ACCD) - 3B-23	Always	Below 1 Ω
   3B-7 - Body ground	Always	Below 1 Ω
   H56-4 (ACCD) or 3B-23 - Body ground	Always	10 kΩ or higher

Result:  NG

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result:  OK

OK 

See step  4

1. Remove the instrument panel junction block assembly. (Refer to REMOVAL (07/2015 -) )

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   TEXT IN ILLUSTRATION
   
   

   *a

   Component without harness connected (Instrument Panel Junction Block Assembly)

   -

   -

2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly. (Refer to REMOVAL (07/2015 -) )
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   3E-1 - 3B-37 3E-1 - 3A-32	Battery voltage not applied to terminals 3B-23 and 3B-7	10 kΩ or higher
   	Battery voltage applied to terminals 3B-23 and 3B-7	Below 1 Ω

Result:  NG

NG 

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

Result:  OK

OK 

See step  5

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Reconnect the H56 certification ECU (smart key ECU assembly) connector.
2. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   H56-4 (ACCD) - Body ground	Engine switch off → Engine switch on (ACC)	1 V or less → 8.5 V or higher

   TEXT IN ILLUSTRATION
   
   

   *a	Component with harness connected (Certification ECU (Smart Key ECU Assembly)

Result:  OK

OK 

USE SIMULATION METHOD TO CHECK 

(Refer to HOW TO PROCEED WITH TROUBLESHOOTING (07/2015 -) )

Result:  NG

NG 

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

(Refer to REMOVAL (07/2015 -) )