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DTC C120C: Linear Solenoid Power Supply System Malfunction [08/2020 - ]: Description

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This DTC is output by the 4WD ECU assembly if a malfunction occurs in the linear solenoid power supply system.

DTC No. Detection Item DTC Detection Condition Trouble Area
C120C Linear Solenoid Power Supply System Malfunction
  1. When the 4WD relay is on, the 4WD relay monitor remains off for 1 second or more while the voltage at the IG1 terminal is 9.5 V or more
  2. When the 4WD relay is on, the 4WD relay monitor remains off for 1 second or more while the voltage at the IG1 terminal is less than 9.5 V
  3. While the 4WD relay is off, the 4WD relay monitor remains on for 1 second or more immediately after the engine switch is turned on (IG)
  • Wire harness or connector
  • 4WD ECU assembly
DTC DETECTION CONDITIONS: C120C

  Vehicle Condition
Pattern 1 Pattern 2 Pattern 3
Diagnosis Condition When the 4WD relay is on and the voltage at the IG1 terminal is 9.5 V or more - -
When the 4WD relay is on and the voltage at the IG1 terminal is less than 9.5 V - -
While the 4WD relay is off - -
Malfunction Status The 4WD relay monitor remains off -
The 4WD relay monitor remains on immediately after the engine switch is turned on (IG) - -
Detection Time 1 second or more 1 second or more 1 second or more
Number of Trips 1 trip 1 trip 1 trip

HINT: 

DTC will be output when conditions for any of the patterns in the table above are met.