Description
The battery supplies electricity to the ecm even when the ignition switch is in the off position. 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. When the engine is next started, the ecm illuminates the mil and sets the dtc.
Hint:
If dtc p0560 is set, the ecm does not store other dtcs or the data stored in the ecm are partly erased.
Monitor strategy
Typical enabling conditions
Typical malfunction thresholds
Wiring diagram
Inspection procedure
Hint:
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. 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.
Standard resistance:
below 1
Standard resistance (check for open)
Standard resistance (check for short)
Standard resistance (check for open)
Standard resistance (check for short)
Ok: battery is not depleted
Ok: battery terminals are not loose or corroded
Canister
Components
removal
Disconnect cable from negative battery
terminal
Caution:
Wait at least 90 seconds after disconnecting the
cable from the negative (-) battery terminal to
prevent airbag and seat belt pretensioner activation.
Remove canister
Disconnect the 2 tubes, hose a ...
Registration
Notice:
The vehicle identification number (vin) must be input
into the replacement ecm.
Hint:
The vin is a 17-digit alphanumeric number. The intelligent
tester is required to register the vin.
Description
This registration section consists of 3 parts: input
instructions, read vin and wr ...
Evaporative emission system switching valve control
Dtc summary
Hint:
The vent valve is built into the canister pump module.
Description
The description can be found in the evap (evaporative emission) system (see
page es-335).
Inspection procedure
Refer to the evap system (see page es-340).
Monitor description
5 Hours* after the ign ...