DTC 45 Intake Manifold Pressure Signal

WARNING: This page is about a different variant/trim than selected.

DIAGNOSIS:

The input signal circuit of TCM from ECM is open or shorted.

TROUBLE SYMPTOM:

Excessive shift shock.

WIRING DIAGRAM:

Fig 1: TCM Input Signal - Wiring Diagram

Courtesy of SUBARU OF AMERICA, INC.

DIAGNOSTIC PROCEDURE CHART

Step	Check	Yes	No
1 CHECK ENGINE GROUND TERMINALS AND GROUND CIRCUIT OF ECM < Ref. to DTC 31 THROTTLE POSITION SENSOR , Diagnostic Procedure with Diagnostic Trouble Code (DTC). >	Is there any trouble?	Repair the ground terminal and/or ground circuit of ECM.	Go to step 2.
2 CHECK HARNESS CONNECTOR BETWEEN TCM AND ECM. Turn the ignition switch to OFF. Disconnect the connectors from TCM and ECM. Measure the resistance of harness between TCM and ECM connector. Connector & terminal (B54) No. 20 - (B137) No. 2:	Is the resistance less than 1 Ω?	Go to step 3.	Repair the open circuit in harness between TCM and ECM connector.
3 CHECK HARNESS CONNECTOR BETWEEN TCM AND ECM. Measure the resistance of harness between TCM connector and chassis ground. Connector & terminal (B55) No. 20 - Chassis ground:	Is the resistance more than 1 MΩ?	Go to step 4.	Repair the short circuit in harness between TCM and ECM connector.
4 PREPARE SUBARU SELECT MONITOR.	Do you have a Subaru Select Monitor?	Go to step 6.	Go to step 5.
5 CHECK INPUT SIGNAL FOR TCM. Connect the connectors to TCM and ECM. Start the engine, and warm-up the transmission 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. Idle the engine. Measure the voltage between TCM connector and chassis ground. Connector & terminal (B55) No. 20 (+) - Chassis ground (-):	Is the voltage 0.4 - 1.6 V?	Even if the AT OIL TEMP warning light blinks, the circuit has returned to a normal condition at this time. A temporary poor contact of the connector or harness may be the cause. Repair the harness or connector in TCM and ECM.	Go to step 7.
6 CHECK INPUT SIGNAL FOR TCM USING SUBARU SELECT MONITOR. Connect the connectors to TCM and ECM. Connect the Subaru Select Monitor to data link connector. Start the engine, and turn Subaru Select Monitor switch to ON. Warm-up the engine until engine coolant temperature is above 80°C (176°F). Idle the engine. Read the data of intake manifold pressure signal using Subaru Select Monitor. Display shows the intake manifold pressure signal value sent from ECM.	Is the value voltage 0.4 - 1.6 V?	Even if the AT OIL TEMP warning light blinks, the circuit has returned to a normal condition at this time. A temporary poor contact of the connector or harness may be the cause. Repair the harness or connector in TCM and ECM.	Go to step 7.
7 CHECK POOR CONTACT.	Is there poor contact in intake manifold pressure signal circuit?	Repair the poor contact.	Replace the TCM. < Ref. to TRANSMISSION CONTROL MODULE (TCM) . >