EN(H4SO 2.0)(diag)-193
ENGINE (DIAGNOSTICS)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
7
CHECK SENSOR OUTPUT.
Measure the voltage between ECM connector
terminals.
Connector & terminal
(B137) No. 23 (+) — (B136) No. 18 (
−
):
Is the voltage less than 4.8 V? Go to step 8.
Go to step 9.
8
CHECK POOR CONTACT.
Check poor contact in connector between
ECM and electronic throttle control.
Is there poor contact?
Repair the poor
contact.
Go to step 13.
9
CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Disconnect the connectors from electronic
throttle control.
4) Measure the resistance between ECM con-
nector and electronic throttle control connector.
Connector & terminal
(B137) No. 23 — (E78) No. 5:
(B137) No. 24 — (E78) No. 2:
LHD model
(B136) No. 17 — (E78) No. 4:
RHD model
(B136) No. 17 — (E78) No. 6:
Is the resistance less than 1
Ω?
Go to step 10.
Repair the open
circuit of harness
connector.
10
CHECK HARNESS BETWEEN ECM AND
ELECTRONIC THROTTLE CONTROL.
Measure the resistance between ECM connec-
tor and chassis ground.
Connector & terminal
(B136) No. 17 — Chassis ground:
(B137) No. 23 — Chassis ground:
(B137) No. 24 — Chassis ground:
Is the resistance more than 1
M
Ω?
Go to step 11.
Repair the ground
short circuit of har-
ness.
11
CHECK SENSOR POWER SUPPLY.
1) Connect the ECM connector.
2) Turn the ignition switch to ON.
3) Measure the voltage between electronic
throttle control connector and engine ground.
Connector & terminal
LHD model
(E78) No. 4 (+) — Engine ground (
−
):
RHD model
(E78) No. 6 (+) — Engine ground (
−
):
Is the voltage 4.5 — 5.5 V?
Go to step 12.
Repair the poor
contact in ECM
connector.
Replace the ECM
if defective. <Ref.
to FU(H4SO 2.0)-
34, Engine Con-
trol Module
(ECM).>
12
CHECK SHORT CIRCUIT INSIDE THE ECM.
1) Turn the ignition switch to OFF.
2) Measure the resistance between electronic
throttle control connector and engine ground.
Connector & terminal
(E78) No. 2 — Engine ground:
(E78) No. 5 — Engine ground:
Is the resistance more than 10
Ω?
Go to step 13.
Repair the poor
contact in ECM
connector.
Replace the ECM
if defective. <Ref.
to FU(H4SO 2.0)-
34, Engine Con-
trol Module
(ECM).>
13
CHECK SENSOR OUTPUT.
1) Connect all the connectors.
2) Turn the ignition switch to ON.
3) Read the data of main throttle sensor signal
using Subaru Select Monitor.
NOTE:
For detailed operation procedure, refer to
“READ CURRENT DATA FOR ENGINE”. <Ref.
to EN(H4SO 2.0)(diag)-25, Subaru Select Mon-
itor.>
Is the voltage 0.5 — 1.0 V?
Go to step 14.
Go to step 16.
Step
Check
Yes
No