Subaru Legacy 2004 Service Manual page 4073

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
E: DTC P1574 KEY COMMUNICATION FAILURE
DTC DETECTING CONDITION:
Failure of body integrated unit to verify key (transponder) ID code
Step
1 CHECK BODY INTEGRATED UNIT FUNC-
TION.
Insert the key to ignition switch (LOCK posi-
tion), and measure the changes in voltage
between antenna connectors.
Connector & terminal
(B142) No. 1 — No. 2:
2 CHECK IGNITION KEY (TRANSPONDER).
1) Remove the key from ignition switch.
2) Start the engine using other keys that have
undergone the teaching operation, furnished
with vehicle.
F: DTC P1576 EGI CONTROL MODULE EEPROM
DTC DETECTING CONDITION:
ECM malfunctioning
1. REPLACE ECM
Replace the ECM. <Ref. to FU(H4SO 2.0)-34, Engine Control Module (ECM).> <Ref. to FU(H4SO 2.5)-36,
Engine Control Module (ECM).> <Ref. to FU(H4DOTC)-35, Engine Control Module (ECM).> <Ref. to
FU(H6DO)-34, Engine Control Module (ECM).>
Perform the registration procedure next. Refer to "REGISTRATION MANUAL FOR IMMOBILIZER".
G: DTC P1577 IMM CONTROL MODULE EEPROM
DTC DETECTING CONDITION:
Body integrated unit malfunctioning
1. REPLACE BODY INTEGRATED UNIT
Replace the body integrated unit <Ref. to SL-46, Body Integrated Unit.> and replace the all ignition keys (in-
cluding transponder). Execute the registration procedure next. Refer to "REGISTRATION MANUAL FOR IM-
MOBILIZER".
Check
Is the voltage #30 to 30 V?
(Approx. 0.1 second after
inserting the key) Is the voltage
0 V? (Approx. 1 second after
inserting the key)
Does the engine start?
IM(diag)-25
IMMOBILIZER (DIAGNOSTICS)
Yes
Go to step 2. Replace the body
integrated unit
<Ref. to SL-46,
Body Integrated
Unit.> and replace
the all ignition keys
(including tran-
sponder). Execute
the registration
procedure next.
Refer to "REGIS-
TRATION MAN-
UAL FOR
IMMOBILIZER".
Replace all the Replace the body
ignition keys integrated unit
(including tran- <Ref. to SL-46,
sponder). Execute Body Integrated
the registration Unit.> and replace
procedure next. the all ignition keys
Refer to "REGIS- (including tran-
TRATION MAN- sponder). Execute
UAL FOR the registration
IMMOBILIZER". procedure next.
Refer to "REGIS-
TRATION MAN-
UAL FOR
IMMOBILIZER".
No