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Home >> Subaru >> 2016 >> BRZ Series.HyperBlue >> Repair and Diagnosis >> Engine Mechanical >> Starter >> Entry Start System Start System (Keyless Start) >> Entry & Start System (Start Function) >> DTC B2274: ACC Circuit Abnormal >> Circuit description
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Circuit description

This DTC is output when a problem is detected in the ACC output circuit between the ACC output terminal of the collation ECM (smart key ECM assembly) and the ACC relay.

NOTE: If you remove and then reconnect the battery cable, the power returns to the mode it was before you removed the cable.
DTC DETECTION CONDITION

DTC No. DTC detection status Faulty part DTC Output Confirmation Operation
B2274 There is a problem in the ACC relay drive circuit in the vehicle exterior circuit or in the collation ECM (smart key ECM assembly) (1 trip detection logic (1)).
NOTE: If the terminal ACCD voltage is not the standard value, the system can cause problems.
  • AM2 No. 2 fuse
  • Instrument panel junction block assembly (ACC relay)
  • Collation ECM (smart key ECM assembly)
  • Wiring harness or connector
 Turn the engine switch on (ACC) or on (IG) and wait 10 seconds, turn the engine switch off, and wait 10 seconds.
NOTE: To turn the engine switch on (ACC), hold the key, move the shift lever in P or N (2), remove your foot from the brake pedal (2) or the clutch (3), and press the engine switch 2 times.
(1) The code is output only when the problem is found and the engine switch is on (IG).
(2) With automatic transmission
(3) With manual transmission

Vehicle status and failsafe upon detection

VEHICLE STATUS AND FAILSAFE UPON DETECTION

Vehicle status when a problem is detected Failsafe function when a problem is detected
  • If a problem occurs when the relay is stuck on, even after you turn the power off, the ACC relay will not turn off.
  • If a problem occurs when the relay is stuck off, even after you turn the engine switch on, the ACC relay will not turn on.
NOTE: You can turn the engine switch on (IG), and start the engine.
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Related [Current Data Display & Save] and [System Operation Check Mode] items

DTC DESCRIPTION

DTC No. [Current Data Display & Save] items [System Operation Check Mode] items
B2274 Power supply
  • [ACC relay monitor]

Engine
  • [Ignition]
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