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DTC B2271: Ignition Hold Monitor Malfunction [10/2015 - ]: Description

This DTC is stored when a malfunction in the IG drive circuit or IG hold circuit of the certification ECU (smart key ECU assembly) or a malfunction in the IG output circuit between the output terminal of the certification ECU (smart key ECU assembly) and IG relay is detected.

DTC No. Detection Item DTC Detection Condition Trouble Area Note
B2271 Ignition Hold Monitor Malfunction When either of the following conditions is met (1-trip detection logic*1):
  • The IG circuit of the certification ECU (smart key ECU assembly) is malfunctioning.*2
  • The IG hold circuit of the certification ECU (smart key ECU assembly) is malfunctioning.*3
  • There is a malfunction in a circuit outside of the certification ECU (smart key ECU assembly) circuit
  • AM2 fuse
  • Certification ECU (smart key ECU assembly)
  • Instrument panel junction block assembly
  • Semiconductor power integration ECU
  • Wire harness or connector
 DTC Output Confirmation Operation: 
  1. Turn the power switch on (IG).
  1. *1: Only detected while a malfunction is present and the power switch is on (IG).
  2. *2: The IG circuit and IG hold circuit activate the IG relay.
  3. *3: After the IG circuit turns on, even if the certification ECU (smart key ECU assembly) malfunctions, the IG hold circuit will maintain the power source mode in on (IG).
VEHICLE CONDITION AND FAIL-SAFE FUNCTION WHEN MALFUNCTION DETECTED

Vehicle Condition when Malfunction Detected Fail-safe Function when Malfunction Detected
The power switch cannot be turned on (IG) (the hybrid control system cannot be started). The power source mode cannot be changed to on (IG).
RELATED DATA LIST AND ACTIVE TEST ITEMS

DTC No. Data List and Active Test
B2271 Power Source Control 
  • IG Relay Monitor (Inside)
  • Latch Circuit
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