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Home >> Subaru >> 2022 >> Ascent Base >> Repair and Diagnosis (Single Page) >> Body & Frame >> Door Locks >> Security And Locks - Keyless Access (W/Push Button Start) (Diagnostics) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC B1577: IMM Control Module EEPROM >> Except For Co Model
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Except For Co Model

DTC detecting condition: 

Trouble symptom: 

Engine cannot be started.

CAUTION:
  • For replacement procedure of keyless access control module, refer to the "REGISTRATION MANUAL FOR IMMOBILIZER" provided as a separate volume. 
  • Before performing diagnosis, refer to "CAUTION" in "General Description". Ref. to KEYLESS ACCESS WITH PUSH BUTTON START (DIAGNOSTICS)>General Description> CAUTION  . 
  1. CHECK DTC  .
    1. Turn the ignition switch to ON.
    2. Using the Subaru Select Monitor, perform the clear memory of [Engine]. Ref. to COMMON (diag)>CLEAR MEMORY .
    3. Turn the ignition switch to OFF.
    4. Remove and install the battery. Ref. to REPAIR CONTENTS>NOTE>BATTERY>GROUND TERMINAL REMOVAL OR INSTALLATION .
    5. Turn the ignition switch to ON.
    6. After 5 seconds or more elapse, read the DTC of [Engine] using the Subaru Select Monitor. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>Diagnostic Trouble Code (DTC) .

    Is DTC B1577 displayed? (Current malfunction)

    Yes  : Replace the keyless access control module. Ref. to SECURITY AND LOCKS>KEYLESS ACCESS CONTROL MODULE .

    No  : Even if DTC is displayed, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

    NOTE:

    In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.