When the Ignition is turned OFF, the 4WD ECU saves some data for the next IG ON.
If a power supply is suspended into the 4WD ECU before IG OFF, the 4WD ECU sets P1779 and lets a warning lamp turn on.
Item
Detecting Condition
Possible cause
DTC Strategy
Checking IG voltage and battery voltage
Poor connection
Open or short in IG ON circuit
When disconnecting 4WD ECU with IG ON
Enable conditions
IG " ON " or Engine " ON "
Diagnostic Time
Immediately
Threshold value
Before IG OFF, the battery power supply is suspended.