Subaru Impreza 2003 Service Manual page 1479

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
• RHD model
MAIN RELAY
4
6
5
3
2
1
B47
E
B72
1 2
3 4
Step
1 CHECK INPUT SIGNAL FOR ECM.
1)Turn the ignition switch to OFF.
2)Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B137) No. 10 (+) — Chassis ground ( − − − − ):
2 CHECK HARNESS BETWEEN ECM AND
MAIN FUSE BOX CONNECTOR.
1)Disconnect the connector from ECM.
2)Measure the resistance of harness between
ECM and chassis ground.
Connector & terminal
(B137) No. 10 — Chassis ground:
DATA LINK CONNECTOR
No.11
A :
B134
D : B136
ECM
E : B137
C :
B84
B22
E3
E
B47 B22
1 2 3 4
1 2
5 6 7 8
3 4
5 6 9 10 11 12
13 14 15 16
EN(H4DOTC)-303
IGNITION
B72
SWITCH
SBF-4
4 1
B134
1 2 3 4 5 6 7
1 2
8 9 10 11 12 13 14 15
8 9 10 11 12
16 17 18 19 20 21 22
17 18 19 20 21
B136
1 2 3 4 5 6
7 8 9 10 11 12
13 14 15 16 17
Check
Is the voltage more than 10 V? Repair the poor
Is the resistance less than 10
Ω?
ENGINE (DIAGNOSTICS)
SBF-5
BATTERY
SBF-1
B137 B84
3 4 1 2 3 4
5 6 7
10 11 12 13 14 15 16 17
13 14 15 16
22 23 24 22 23 24 25 26
Yes
Go to step 2.
contact in ECM
connector.
Repair the ground Go to step 3.
short circuit in har-
ness between
ECM connector
and battery termi-
nal.
E
5 6 7 8 9
18 19 20 21
27 28 29 30 31
EN-01293
No