DTC B2274 ACC Monitor Malfunction: Wiring Diagram

WARNING: This page is about a different car, the 2006 Lexus IS 350. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Wiring Diagram - ACC Monitor Malfunction

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

CHECK WIRE HARNESS (COWL SIDE J/B RH - POWER SOURCE CONTROL ECU AND BODY GROUND)

Disconnect the RD J/B connector.
Disconnect the J55 ECU connector.

Measure the resistance of the wire harness side connectors.

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection (Symbols)	Specified Condition
RD-2 - J55-11 (ACCD)	Below 1 Ω
RD-2 or J55-11 (ACCD) - Body ground	10 kΩ or higher
RD-5 - Body ground	Below 1 Ω
RD-7 - Body ground	Below 1 Ω

Fig 2: Identifying RD J/B Connector (Cowl Side)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR

OK : GO TO NEXT STEP

CHECK COWL SIDE JUNCTION BLOCK RH (ACC RELAY)

Disconnect the RN J/B connector.

Measure the resistance of the J/B connectors.

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
RN-1 - RD-27 or RD-26	When battery voltage is not applied to terminals RD-2 and RD-7 or RD-5	10 kΩ or higher
RN-1 - RD-27 or RD-26	When battery voltage is applied to terminals RD-2 and RD-7 or RD-5	Below 1 Ω

Result

RESULT CHART

Result	Proceed to
NG	A
OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE)	B
OK (When troubleshooting according to the DTC chart)	C

Fig 3: Identifying RN J/B Connector (Cowl Side)

B : PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

C : REPLACE POWER SOURCE CONTROL ECU

A : REPLACE COWL SIDE JUNCTION BLOCK RH