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Home >> Subaru >> 2021 >> Forester Base >> Repair and Diagnosis >> Transmission >> Automatic Trans >> Automatic Transaxle System (Diagnostics) >> Transmission Control Module (TCM) I/O Signal >> Electrical Specification
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Electrical Specification

G11257595Courtesy of SUBARU OF AMERICA, INC.
CAUTION: Use the check board when measuring the TCM terminal.
NOTE: Measure after warming up.
Terminal No. Contents Measuring condition Standard Note
1 ←→ Chassis ground ATF temperature sensor GND Always 0 V -
2 ←→ Chassis ground Secondary pressure sensor GND Always 0 V -
5 ←→ 2 Secondary pressure sensor Ignition switch ON, engine OFF Approx. 0.5 V (0 MPa) Value increases with increase of engine load. (0.5 - 4.5 V)
Engine ON and idle Approx. 1.0 V (1.0 MPa)
6 ←→ 1 ATF temperature sensor ATF temperature at 20°C (68°F) Approx. 2.5 V Approx. 2.5 kΩ
ATF temperature at 80°C (176°F) Approx. 0.7 V Approx. 330 Ω
7 ←→ 26 or 42 Electric oil pump operation status signal Engine ON 0 or battery voltage Refer to waveform (1). Ref. to AUTO START STOP (DIAGNOSTICS)>CONTROL MODULE I/O SIGNAL>WAVEFORM
During Auto Start Stop 0 or battery voltage Refer to waveform (3). Ref. to AUTO START STOP (DIAGNOSTICS)>CONTROL MODULE I/O SIGNAL>WAVEFORM
In malfunction 0 or battery voltage Electric oil pump abnormality DUTY: 60 - 90%
8 ←→ 26 or 42 Main power supply Ignition switch ON Battery voltage -
12 ←→ 26 or 42 Turbine speed sensor Engine ON, "P" or "N" range 0 or 5 V Refer to the waveform (sensor)
13 ←→ 26 or 42 Secondary speed sensor While driving 0 or 5 V Refer to the waveform (sensor)
14 ←→ 26 or 42 Primary speed sensor While driving 0 or 5 V Refer to the waveform (sensor)
15 ←→ 26 or 42 Lock-up duty solenoid Lock-up ON Refer to the waveform (solenoid (5)) Resistance: Approx. 10 - 14.2 Ω Resistance value at 20°C (68°F).
Value is higher as the temperature increase.
16 ←→ 26 or 42 F&R solenoid Engine ON Refer to the waveform (solenoid (1)) Resistance: Approx. 3.5 - 7.1 Ω
Resistance value at 20°C (68°F).
Value is higher as the temperature increase.
18 ←→ 26 or 42 Manual mode down switch*1 Ignition switch ON, Manual mode down switch ON 0 V -
Ignition switch ON, Manual mode down switch OFF Battery voltage
19 ←→ 26 or 42 Manual mode up switch(1) Ignition switch ON, Manual mode up switch ON 0 V -
Ignition switch ON, Manual mode up switch OFF Battery voltage
20 ←→ 26 or 42 Lo/Manual mode switch Ignition switch ON, L range switch/Manual mode switch ON 0 V -
Ignition switch ON, L range switch/Manual mode switch OFF Battery voltage
21 ←→ 26 or 42 Electric oil pump operation command signal Engine ON 0 or battery voltage Refer to waveform (2). Ref. to AUTO START STOP (DIAGNOSTICS)>CONTROL MODULE I/O SIGNAL>WAVEFORM
During Auto Start Stop 0 or battery voltage Refer to waveform (4). Ref. to AUTO START STOP (DIAGNOSTICS)>CONTROL MODULE I/O SIGNAL>WAVEFORM
22 ←→ 26 or 42 Electric oil pump relay drive Ignition switch ON 0 V -
When approx. 3 seconds pass since ignition switch was turned to OFF Battery voltage -
23 ←→ 26 or 42 Start command circuit Except during restarting (from Auto Start Stop release to engine ON) Battery voltage -
During restarting (from Auto Start Stop release to engine ON) 0 V -
24 ←→ 26 or 42 Main power supply Ignition switch ON Battery voltage -
26 ←→ Chassis ground GND Always 0 V -
29 ←→ 26 or 42 Stop light switch Stop light switch ON Battery voltage -
Stop light switch OFF 0 V
30 ←→ 26 or 42 Primary DOWN solenoid Engine ON, while DOWN shifting Refer to the waveform (solenoid (4)) Resistance: Approx. 10 - 14.2 Ω
Resistance value at 20°C (68°F). Value is higher as the temperature increase.
32 ←→ 26 or 42 Secondary solenoid Engine ON Refer to the waveform (solenoid (2)) Resistance: Approx. 4.8 - 8.4 Ω
Resistance value at 20°C (68°F). Value is higher as the temperature increase.
33 ←→ 2 Secondary pressure sensor power supply output Ignition switch ON 5 V -
34 ←→ 26 or 42 Backup power supply Always Battery voltage -
35 ←→ 26 or 42 D range switch Ignition switch ON, D range 0 V -
Ignition switch ON, other than D range Battery voltage  
36 ←→ 26 or 42 N range switch Ignition switch ON, N range 0 V -
Ignition switch ON, other than N range Battery voltage
37 ←→ 26 or 42 R range switch Ignition switch ON, R range 0 V -
Ignition switch ON, other than R range Battery voltage
38 ←→ 26 or 42 P range switch Ignition switch ON, P range 0 V -
Ignition switch ON, other than P range Battery voltage
40 ←→ 26 or 42 Main power supply Ignition switch ON Battery voltage -
41 ←→ 26 or 42 Ignition switch Ignition switch ON Battery voltage -
42 ←→ Chassis ground GND Always 0 V -
43 CAN communication line (+) - - -
44 CAN communication line (-) - - -
45 ←→ 26 or 42 Starter SW At cranking Battery voltage -
Except at cranking 0 V -
47 ←→ 26 or 42 Primary UP solenoid Engine ON, while UP shifting Refer to the waveform (solenoid (3)) Resistance: Approx. 10 - 14.2 Ω
Resistance value at 20°C (68°F). Value is higher as the temperature increase.
48 ←→ 26 or 42 AWD solenoid Engine ON, "P" or "N" range Refer to the waveform (solenoid (6)) Resistance: Approx. 1.5 - 4.9 Ω
Resistance value at 20°C (68°F).
Value is higher as the temperature increase.
Engine ON, "D" range, brake ON Refer to the waveform (solenoid (7))
(1) With paddle shift switch