Subaru Impreza 2002 Service Manual page 3597

DIAGNOSTICS CHART WITH DIAGNOSTIC TROUBLE CODE (DTC)
IMMOBILIZER (DIAGNOSTICS)
Step
7 CHECK HARNESS OF COMMUNICATION
LINE.
Measure the voltage between ECM harness
connector terminal and engine ground.
Connector & terminal
Non-turbo engine model
(B135) No. 22, No.23 (+) — Engine
ground ( − − − − ):
Turbo engine model
(B135) No. 5, No.14 (+) — Engine
ground ( − − − − ):
8 CHECK ECM BY INTERFACE CHECK.
1)Connect the harness connector to ECM.
2)Disconnect the harness connector from IMM
ECM.
3)Perform interface check. <Ref. to IM-7,
INTERFACE CHECK, Subaru Select Monitor.>
9 CHECK ECM BY INTERFACE CHECK.
Perform interface check.
10 CHECK ECM BY INTERFACE CHECK.
Perform interface check.
Check
Is the voltage 0 V?
Does "Commun. Line Shorted
to Ground" appear on the
screen?
Does "Commun. Line Shorted
to Battery" appear on the
screen?
Does "Communication Line not
Shorted" appear on the
screen?
IM-20
Yes
Go to step 8. Repair the har-
ness between IMM
ECM and ECM,
because there is
short circuit with
battery voltage line
or ignition switch
"ON" line.
Replace the ECM. Go to step 9.
<Ref. to FU-51,
Engine Control
Module.>, <Ref. to
FU(w/oOBD)-48,
Engine Control
Module.> or <Ref.
to FU(TURBO)-49,
Engine Control
Module.> Then
perform teaching
operation. Refer to
the teaching oper-
ation manual (Pub.
No. S0820GZ).
Replace the ECM. Go to step 10.
<Ref. to FU-51,
Engine Control
Module.>, <Ref. to
FU(w/oOBD)-48,
Engine Control
Module.> or <Ref.
to FU(TURBO)-49,
Engine Control
Module.> Then
perform teaching
operation. Refer to
the teaching oper-
ation manual (Pub.
No. S0820GZ).
Replace the IMM When "Check
ECM <Ref. to SL- (Time Out)"
34, Immobilizer appears on the
Control Module.> screen, perform
and then replace interface check
all ignition keys again.
(including the tran-
sponder). Then
perform teaching
operation. Refer to
the teaching oper-
ation manual (Pub.
No. S0820GZ).
No