MONITOR DESCRIPTION
The battery supplies electricity to the ECM even when the engine 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). |
| Comes on | DTC stored | SAE Code: P0562 |
MONITOR STRATEGY
Related DTCs | P0562: ECM system voltage range check (low voltage) |
Required Sensors/Components (Main) | ECM |
Required Sensors/Components (Related) | - |
Frequency of Operation | Continuous |
Duration | 3 seconds |
MIL Operation | Immediate |
Sequence of Operation | None |
TYPICAL ENABLING CONDITIONS
Monitor runs whenever the following DTCs are not stored | None |
All of the following conditions are met | - |
Battery voltage | 8 V or higher |
Engine switch | On (IG) |
Starter | Off |
TYPICAL MALFUNCTION THRESHOLDS
Both of the following conditions are met | - |
Battery voltage (BATT) | Less than 3.5 V |
Electronic throttle actuator power supply voltage (+BM) | Less than 3.5 V |
CONFIRMATION DRIVING PATTERN
HINT:
Click here
Click here
HINT:
Techstream Display | Description |
---|---|
NORMAL |
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ABNORMAL |
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INCOMPLETE |
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HINT:
The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Click here
HINT:
Read freeze frame data using the Techstream. 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
1. | INSPECT BATTERY |
(a) Inspect the battery.
Click here
OK:
Battery voltage is between 11 to 14 V.
NG | ![]() | CHARGE OR REPLACE BATTERY |
|
2. | CHECK BATTERY TERMINAL |
(a) Check that the battery terminals are not loose or corroded.
OK:
Battery terminals are not loose or corroded
NG | ![]() | REPAIR OR REPLACE BATTERY TERMINAL |
|
3. | CHECK HARNESS AND CONNECTOR (POWER SOURCE OF ECM) |
*a | Front view of wire harness connector (to ECM) |
(a) Disconnect the ECM connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Condition | Specified Condition |
---|---|---|
A37-1 (BATT) - Body ground | Always | 11 to 14 V |
A37-8 (+BM) - Body ground | Always | 11 to 14 V |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - ECM) |
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4. | CHECK WHETHER DTC OUTPUT RECURS (DTC P056014) |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Clear the DTCs.
Powertrain > Engine > Clear DTCs(e) Turn the engine switch off and wait for at least 30 seconds.
(f) Turn the engine switch on (IG).
(g) Turn the Techstream on.
(h) Wait 5 seconds or more.
(i) Enter the following menus: Powertrain / Engine / Trouble Codes.
(j) Read the DTCs.
Powertrain > Engine > Trouble Codes Result | Proceed to |
---|---|
DTCs are not output | A |
DTC P056014 is output | B |
A | ![]() | CHECK FOR INTERMITTENT PROBLEMS |
B | ![]() | REPLACE ECM |
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