DTC    B2274    ACC Monitor Malfunction

for Preparation Click here


DESCRIPTION

This DTC is stored when there is a problem in the ACC output circuit. The ACC circuit is the circuit that goes from inside the power management control ECU to the ACC relay.

HINT:
  1. When the power management control ECU is replaced with a new one and the cable is connected to the negative (-) auxiliary battery terminal, the power source mode changes to on (IG).
  2. When the auxiliary battery cable is disconnected and reconnected, the power source returns to the mode it was in before the auxiliary battery cable was disconnected.

This DTC is stored when a malfunction in the ACC output circuit between the ACC output terminal of the power management control ECU and the ACC relay is detected.

DTC Code
DTC Detection Condition
Trouble Area
DTC Output Confirmation Operation
B2274
Malfunction in the ACC relay activation circuit in the power management control ECU or the external circuit (1-trip detection logic*).

HINT:
When the voltage at terminal ACCD is not at the standard, the system is determined to be malfunctioning.

  1. AM2 fuse
  2. ACC relay (Instrument panel junction block assembly)
  3. Power management control ECU
  4. Wire harness or connector
Wait 10 seconds after turning the power switch on (ACC) or on (IG), and then wait another 10 seconds after turning the power switch off.

HINT:
To turn the power switch on (ACC), carry the key and press the power switch with the park (P) selected and the brake pedal released.

  1. *: Only output while a malfunction is present and the power switch is on (IG)

Vehicle Condition and Fail-safe Function when Malfunction Detected 
Vehicle Condition when Malfunction Detected
Fail-safe Function when Malfunction Detected
  1. If there is a malfunction when the relay is stuck on, the ACC relay does not turn off even though all the power is off.
  2. If there is a malfunction when the relay is off, the ACC relay does not turn on even though the power source mode is on (ACC).

HINT:
The power source can change to on (IG) and the hybrid control system can be started.

-

WIRING DIAGRAM


B231374E06


INSPECTION PROCEDURE

NOTICE:
  1. When using the intelligent tester with the power switch off, perform either of the following: 1) Turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the intelligent tester and vehicle begins, or 2) connect the intelligent tester to the vehicle, select the vehicle type under manual mode, and then enter the following menus:
    for Power Source Control: Body / Power Source Control / DTC.
    for Entry&Start: Body / Entry&Start / DTC.
  2. The push-button start system uses multiplex communication. First perform the inspections in "How to Proceed with Troubleshooting" to confirm that there are no communication malfunctions before proceeding with troubleshooting (Click here).
  3. Inspect the fuses of circuits related to this system before performing the following inspection procedure.
  4. When the power source mode cannot change to on (ACC), the audio and navigation systems do not operate.
  5. After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.


HINT:

Related Data List and Active Test Items 
DTC
Data List Item
Active Test Item
B2274
Power Source Control
  1. ACC Relay Monitor
-

1.CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - POWER MANAGEMENT CONTROL ECU)
  1. Disconnect the H3 and H4 connectors from the power management control ECU.

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

    Standard Voltage:
    Tester Connection
    Condition
    Specified Condition
    H3-1 (AM22) - Body ground
    Always
    9.5 to 16 V
    H4-7 (AM21) - Body ground
    Always
    9.5 to 16 V



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - BODY GROUND)
  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    H3-5 (E01) - Body ground
    Always
    Below 1 Ω
    H3-6 (E1) - Body ground
    Always
    Below 1 Ω
    H4-4 (E12) - Body ground
    Always
    Below 1 Ω
    H4-5 (E02) - Body ground
    Always
    Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    B231373E15
  1. Remove the instrument panel junction block assembly (Click here).

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    2A-43 - 2B-4
    20°C (68°F)
    81.49 to 118.98 Ω
    2A-43 - 2B-6
    20°C (68°F)
    81.49 to 118.98 Ω
    2B-4 - 2B-6
    Always
    Below 1 Ω

    Text in Illustration 
    *a
    Component without harness connected
    (Instrument Panel Junction Block Assembly)



NG
REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (Click here)
OK


4.CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - INSTRUMENT PANEL J/B)
  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    H4-1 (ACCD) - 2A-43
    Always
    Below 1 Ω
    H4-1 (ACCD) - Body ground
    Always
    10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5.CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - BODY GROUND)
  1. Measure the resistance according to the value(s) the table below.

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    2B-4 - Body ground
    Always
    Below 1 Ω
    2B-6 - Body ground
    Always
    Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


6.INSPECT POWER MANAGEMENT CONTROL ECU


    B229525E11
  1. Install the instrument panel junction block assembly (Click here).

  1. Reconnect the H3 and H4 connectors.

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

    Standard Voltage:
    Tester Connection
    Condition
    Specified Condition
    H4-1 (ACCD) - Body ground
    Power switch on (ACC)
    Output voltage at terminal AM21 or AM22 is -2.5 V or more

    Text in Illustration 
    *a
    Component with harness connected
    (Power Management Control ECU)



NG
REPLACE POWER MANAGEMENT CONTROL ECU (Click here)
OK

USE SIMULATION METHOD TO CHECK (Click here)