Subaru 2002 IMPREZA Service Manual page 1210

ENGINE MALFUNCTION INDICATOR LAMP (MIL)
ENGINE (DIAGNOSTICS)
C: CHECK ENGINE MALFUNCTION INDICATOR LAMP (MIL) DOES NOT COME
ON.
• DIAGNOSIS:
• The CHECK ENGINE malfunction indicator lamp (MIL) circuit is open or shorted.
• TROUBLE SYMPTOM:
• When the ignition switch is turned to ON (engine OFF), MIL does not come on.
• WIRING DIAGRAM:
A7
C6
COMBINATION
METER
A : i10
C :
i12
B72
1 2
3 4
i3
1 2 3 4 5
11 12 13 14 15 16 17 18 19 20 21 22
Step
1 CHECK OUTPUT SIGNAL FROM ECM.
1)Turn the ignition switch to ON.
2)Measure the voltage between ECM connec-
tor and chassis ground.
Connector & terminal
(B137) No. 15 (+) — Chassis ground ( − − − − ):
2 CHECK POOR CONTACT.
No.13
LHD RHD AT
B36 B36
i1 i1
LHD RHD AT
i2
LHD : 16
*
RHD : 13
B37
B137 ECM
C :
i12
1 2 3 4 5 6
7 8 9 10 11 12 13 14
1 2 3 4
12 13 14 15 16 17 18 19 20 21 22 23 24
6 7 8 9 10
1 2 3
7 8 9 10 11 12 13 14
EN(TURBO)-50
IGNITION
B72
SWITCH
SBF-4
4 1
B38
i3
A :
i10
1 2 3 4 5 6 7 8 9 10
B36
5 6 7 8 9 10 11
i1
4 5 6
Check
Is the voltage less than 1 V?
Does the MIL come on when
shaking or pulling ECM con-
nector and harness?
BATTERY
SBF-1
B137
1 2 3 4
5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 27 28 29 30 31
i2
1 2 3 4 5 6 7 8 9 10 11
12 13 14 15 16 17 18 19 20 21 22 23 24
(LHD)
1 2 3 4 5 6 7 8
10 11 12 13 14 15 16 17 18 19 20
22 23 24 25 26 27 28 29 30 31
(RHD)
Yes
Go to step 4. Go to step 2.
Repair the poor Go to step 3.
contact in ECM
connector.
E
9
21
32
EN1426
No