The 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 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.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory | Note |
|---|---|---|---|---|---|---|
| P056014 | System Voltage Circuit Short to Ground or Open | An open or short in the ECM backup power source circuit (1 trip detection logic). | ·
Open or short in back up power source circuit ·
Battery ·
Battery terminals ·
ECM |
Comes on | DTC stored | SAE Code:
P0562 |
| Required Sensors/Components | ECM |
| Frequency of Operation | Continuous |
| Both of the following conditions are met | - |
| Battery voltage (BATT) | Below 3.5 V |
| Electronic throttle actuator power supply voltage (+BM) | Below 3.5 V |
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.
When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the ignition switch off and wait for at least 30 seconds.
Turn the ignition switch to ON [A].
Turn the GTS on.
Wait 5 seconds or more [B].
Enter the following menus: Powertrain / Engine / Trouble Codes [C].
Read the pending DTCs.
If a pending DTC is output, the system is malfunctioning.
If a pending DTC is not output, perform the following procedure.
Enter the following menus: Powertrain / Engine / Utility / All Readiness.
Input the DTC: P056014.
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 |
If the judgment result shows NORMAL, the system is normal.
If the judgment result shows ABNORMAL, the system has a malfunction.
[A] to [C]: 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 battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.
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 (-) battery terminal.
When disconnecting and reconnecting the battery, there is an automatic learning function that completes learning when the respective system is used.
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.
Inspect the battery.
Battery voltage is between 11 to 14 V.
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Check that the battery terminals are not loose or corroded.
Battery terminals are not loose or corroded.
| Proceed to |
|---|
| OK |
| NG |
OK
NG
| *a | Front view of wire harness connector
(to ECM) |
- | - |
Disconnect the ECM connector.
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| A46-1 (BATT) - Body ground | Always | 11 to 14 V |
| C78-48 (+BM) - Body ground | Always | 11 to 14 V |
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Clear the DTCs.
Turn the ignition switch off and wait for at least 30 seconds.
| Proceed to |
|---|
| NEXT |
NEXT
Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine / Trouble Codes.
Read the DTCs.
| Result | Proceed to |
|---|---|
| DTCs are not output | A |
| DTC P056014 is output | B |
A
B