
Dtc summary

Description
To ensure the accuracy of the evap (evaporative emission) monitor values, the soak timer, which is built into the ecm, measures 5 hours (+-15 minutes) from when the ignition switch is turned off, before the monitor is run. This allows the fuel to cool down, which stabilizes the evap pressure. When 5 hours have elapsed, the ecm turns on.

Monitor description
5 Hours after the ignition switch is turned off, the soak timer activates the ecm to begin the evap system monitor. While the engine is running, the ecm monitors the synchronization of the soak timer and the cpu clock. If these two are not synchronized, the ecm interprets this as a malfunction, illuminates the mil and sets the dtc (2 trip detection logic).
Monitor strategy
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Typical enabling conditions

Typical malfunction thresholds
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Inspection procedure
Hint:
Ecm replacement is necessary.

Evaporative emission system switching valve control
A/f sensor circuit slow response (bank 1 sensor 1)Terminals of ecu
Check tire pressure warning ecu
Disconnect the e56 ecu connector.
Measure the voltage and resistance of the wire
harness side connector.
If the result is not as specified, there may be a
malfunction on the wire harness side.
Reconnect the e56 ecu connector.
Measure the ...
System description
Engine immobiliser system description
The engine immobiliser system is designed to prevent
the vehicle from being stolen. This system uses a
transponder key ecu that stores the key codes of
authorized ignition keys. If an attempt is made to start
the engine using an unauthorized key, the e ...
Driver side - side airbag sensor circuit malfunction
Description
The side airbag sensor lh consists of part including the diagnostic circuit
and the lateral deceleration
sensor.
When the center airbag sensor receives signals from the lateral deceleration
sensor, it determines
whether or not the srs should be activated.
Dtc b1620/21 is ...