Subaru 2002 IMPREZA Service Manual page 1631

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
Step
5 CHECK INPUT SIGNAL FOR TCM.
1)Connect the connectors to TCM and ECM.
2)Start the engine and warm-up the transmis-
sion until ATF temperature is above 80°C
(176°F).
NOTE:
If ambient temperature is below 0°C (32°F),
drive the vehicle until ATF reaches its operating
temperature.
3)Idle the engine.
4)Measure the voltage between TCM connec-
tor and chassis ground.
Connector & terminal
(B54) No. 1 (+) — Chassis ground ( − − − − ):
6 CHECK INPUT SIGNAL FOR TCM USING
SUBARU SELECT MONITOR.
1)Connect the connectors to TCM and ECM.
2)Connect the Subaru Select Monitor to data
link connector.
3)Start the engine and turn the Subaru Select
Monitor switch to ON.
4)Warm-up the engine until engine coolant
temperature is above 80°C (176°F).
5)Idle the engine.
6)Read the data of mass air flow sensor signal
using Subaru Select Monitor.
•Display shows the mass air flow sensor signal
value sent from ECM.
7 CHECK POOR CONTACT.
AUTOMATIC TRANSMISSION (DIAGNOSTICS)
Check
Is the voltage between 0.9 and
1.4 V?
Is the value voltage between
0.9 and 1.4 V?
Is there poor contact in intake
manifold pressure signal cir-
cuit?
AT-45
Yes
Even if the AT OIL Go to step 7.
TEMP warning
lights up, the cir-
cuit has returned
to a normal condi-
tion at this time. A
temporary poor
contact of the con-
nector or harness
may be the cause.
Repair harness or
connector in the
TCM and ECM.
Even if the AT OIL Go to step 7.
TEMP warning
lights up, the cir-
cuit has returned
to a normal condi-
tion at this time. A
temporary poor
contact of the con-
nector or harness
may be the cause.
Repair harness or
connector in the
TCM and ECM.
Repair the poor Replace the TCM.
contact. <Ref. to AT-46,
Transmission Con-
trol Module
(TCM).>
No