Toyota Corolla Cross: System Voltage Circuit Short to Ground or Open (P056014)

MONITOR DESCRIPTION

The auxiliary battery supplies electricity to the ECM even when the ignition switch is off. This power allows the ECM to store data such as DTC history, Freeze Frame Data and fuel trim values. If the auxiliary battery voltage falls below a minimum level, the memory is cleared and the ECM determines that there is a malfunction in the power supply circuit. The next time the engine is started, the ECM will illuminate the MIL and store this DTC.

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

CONFIRMATION DRIVING PATTERN

HINT:

• After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

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• When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.

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1. Connect the GTS to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the GTS on.
4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
5. Turn the ignition switch off and wait for at least 30 seconds.
6. Turn the ignition switch to ON.
7. Turn the GTS on.
8. Wait 5 seconds or more [A].
9. Enter the following menus: Powertrain / Engine / Trouble Codes [B].
10. Read the pending DTCs.

    HINT:

    • If a pending DTC is output, the system is malfunctioning.
    • If a pending DTC is not output, perform the following procedure.
11. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
12. Input the DTC: P056014.
13. Check the DTC judgment result.

    GTS Display	Description
    NORMAL	DTC judgment completed System normal
    ABNORMAL	DTC judgment completed System abnormal
    INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions

    HINT:

    • If the judgment result is NORMAL, the system is normal.
    • If the judgment result is ABNORMAL, the system is malfunctioning.
    • [A] to [B]: Normal judgment procedure.

      The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

    • When clearing the permanent DTCs, do not disconnect the cable from the auxiliary battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

• Inspect the fuses for circuits related to this system before performing the following procedure.
• After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.

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• When disconnecting and reconnecting the auxiliary battery.

  HINT:

  When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.

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HINT:

Read Freeze Frame Data using the GTS. The ECM records vehicle and driving condition information as Freeze Frame Data the moment a DTC is stored. When troubleshooting, Freeze Frame Data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE

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OK:

Auxiliary battery voltage is between 11 to 14 V.

NG

CHARGE OR REPLACE AUXILIARY BATTERY

OK

(a) Check that the auxiliary battery terminals are not loose or corroded.

OK:

Auxiliary battery terminals are not loose or corroded.

NG

REPAIR OR REPLACE AUXILIARY BATTERY TERMINAL

OK

(a) Disconnect the ECM connector.

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

Standard Voltage:

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (AUXILIARY BATTERY - ECM)

OK

(a) Clear the DTCs.

(b) Turn the ignition switch off and wait for at least 30 seconds.

NEXT

(a) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

(b) Read the DTCs.

A

CHECK FOR INTERMITTENT PROBLEMS

B

REPLACE ECM

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