Subaru Legacy 2003 Service Manual page 2008

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Step
1 CHECK GENERATOR.
1) Start the engine.
2) Idling after warm-up.
3) Measure the voltage between generator B
terminal and chassis ground.
Terminal
Generator B terminal (+) — Chassis
ground (–):
Does the measured value exceed the spec-
ified value?
2 CHECK GENERATOR.
1) Run the engine at 5,000 rpm.
2) Measure the voltage between generator B
terminal and chassis gorund.
Terminal
Generator B terminal (+) — Chassis
ground ( − − − − ):
Does the measured value exceed the spec-
ified value?
3 CHECK BATTERY TERMINAL.
Turn the ignition switch to OFF.
Are the positive and negative battery terminals
tightly clamped?
4 CHECK INPUT VOLTAGE OF ECM.
1) Run the engine at idle.
2) Measure the voltage between ECM con-
nector and chassis ground.
Connector & terminal
(B136) No. 1 (+) — Chassis ground ( − − − − ):
(B136) No. 2 (+) — Chassis ground ( − − − − ):
Does the measured value exceed the spec-
ified value?
5 CHECK POOR CONTACT IN CONNECTORS.
Is there poor contact in connectors between
generator, battery and ECM?
6 CHECK ECM.
1) Connect all connectors.
2) Erase the memory. <Ref. to
EN(H4DOSTC)-35, Clear Memory Mode.>
3) Perform the inspection mode. <Ref. to
EN(H4DOSTC)-33, Inspection Mode.>
4) Read out the DTC. <Ref. to
EN(H4DOSTC)-32, Read Diagnostic Trou-
ble Code.>
Is the same DTC as in the current diagno-
sis still being output?
7 CHECK ANY OTHER DTCs APPEARANCE.
Are other DTCs being output?
Value
16.2 V
16.2 V
Clamped tightly.
16.2 V
There is poor contact.
DTC indicated.
DTCs indicated.
EN(H4DOSTC)-169
ENGINE (DIAGNOSTICS)
Yes
Go to step 2. Repair the genera-
tor. <Ref. to
SC(H4DOSTC)-
14, Generator.>
Go to step 3. Repair the genera-
tor. <Ref. to
SC(H4DOSTC)-
14, Generator.>
Go to step 4. Tighten the clamp
of terminal.
Go to step 5. Repair the har-
ness connector
between battery,
main relay and
ECM.
Repair the con- Go to step 6.
nector.
Replace the gen- Go to step 7.
erator.
Proceed with the A temporary poor
diagnosis corre- contact.
sponding to the
DTC.
No