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Pin Voltage Charts

NOTE: All voltage tests should be performed with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in testing procedures. Voltage readings may vary slightly due to battery condition or charging rate.
  1. ECU circuits are checked at the ECU connector under one or more of the following conditions: ignition switch off, ignition on and engine off, or ignition on and engine running.
  2. To test pin voltage, carefully backprobe terminal at harness side of ECU connector. Test between indicated terminal No. and body ground. See Fig 1 . Use wire color to help identify terminal. See WIRING COLOR CODE table and ECU CIRCUIT IDENTIFICATION tables.
  3. If resistance or voltage is not as specified, test and repair, or replace, circuit or affected component. See ECU PIN SPECIFICATIONS (XT & XT6) table. Retest circuit to verify repair has been made. Unless stated otherwise, perform all tests with ECU harness connected.
Fig 1: Identifying ECU Connectors Terminals (XT & XT6)
G118424Courtesy of SUBARU OF AMERICA, INC.
XT ECU CONNECTOR TERMINAL IDENTIFICATION

Terminal Color Identification
1 YR Check Connector
2 W Air Flow Meter (Signal)
3 GL Purge Control Solenoid
4 GY Neutral Switch (MT)
" YL Inhibitor Switch (AT)
5 B Air Flow Meter (Ground)
6 LB Fuel Pump Relay
7 R Crank Angle Sensor (Power)
8 B Crank Angle Sensor (Reference)
9 WB Water Temperature Sensor
10 BR Ground
11 N/A N/A
12 W Air flow Meter (Power)
13 N/A N/A
14 N/A N/A
15 Lg Inhibitor Switch (AT)
16 BR Throttle Sensor (Ground)
17 W Crank Angle Sensor (Position Signal)
18 N/A N/A
19 BW Ignition Switch Signal
20 BR Ground
21 W Throttle Sensor (Power Supply)
22 B Throttle Sensor (Signal)
23 L Air Conditioner Signal
24 BW (MT) Starter Signal
" BY (AT) Starter Signal
25 LW Idle Switch Signal
26 N/A N/A
27 WR Control Unit Power (Input)
28 BY Specification Code
29 YR Car-Speed Sensor
30 BR Identification of AT and MT
31 N/A N/A
32 Br Test Mode Connector
33 LgW Read-Memory Connector
34 N/A N/A
35 WR Control Unit Power (Input)
36 N/A N/A
37 WY Ignition Output (Power Transistor)
38 LgR Air Flow Meter (Burn-Off Output)
39 GW Self-Shutoff Output
40 RY CHECK ENGINE Light
41 N/A N/A
42 RB A/C Cut Control
43 WY Ignition Output (Power Transistor)
44 RL Check Connector
45 GB Check Connector
46 L Check Connector
47 R Trouble Code Output
48 W O(2) Sensor
49 W Fuel Injector #1, #2
50 W Fuel Injector #1, #2
51 WL Fuel Injector #3, #4
52 WL Fuel Injector #3, #4
53 N/A N/A
54 N/A N/A
55 W Fuel Pump Control
56 B Ground (Ignition)
57 B Ground (Ignition)
58 N/A N/A
59 G Auxiliary Air Valve Control
60 BR Ground (Fuel Injector)
61 BR Ground (Fuel Injector)
62 R Power (Fuel Injector)
63 N/A N/A
XT6 ECU CONNECTOR TERMINAL IDENTIFICATION

Terminal Color Identification
1 YR Check Connector
2 W Air Flow Meter (Signal)
3 GL Purge Control Solenoid
4 GY Neutral Switch (MT)
" YL Inhibitor Switch (AT)
5 B Air Flow Meter (Ground)
6 LB Fuel Pump Relay
7 R Crank Angle Sensor (Power)
8 B Crank Angle Sensor (Position Signal)
9 WB Water Temperature Sensor
10 BR Ground
11 N/A N/A
12 W Air flow Meter (Power)
13 N/A N/A
14 YW Inhibitor Switch (AT)
15 Lg Inhibitor Switch (AT)
16 BR Throttle Sensor (Ground)
17 W Crank Angle Sensor (Reference)
18 N/A N/A
19 BW Ignition Switch Signal
20 BR Ground
21 W Throttle Sensor (Power Supply)
22 B Throttle Sensor (Signal)
23 L Air Conditioner Signal
24 BW (MT) Starter Signal
" BY (AT) Starter Signal
25 LW Idle Switch Signal
26 N/A N/A
27 WR Control Unit Power (Input)
28 N/A N/A
29 YR Car-Speed Sensor
30 BR Identification of AT and MT
31 LB Specification Code
32 Br Test Mode Connector
33 LgW Read-Memory Connector
34 N/A N/A
35 WR Control Unit Power (Input)
36 R Knock Sensor
37 WY Ignition Output (Power Transistor)
38 LgR Air Flow Meter (Burn-Off Output)
39 GW Self-Shutoff Output
40 RY CHECK ENGINE Light
41 N/A N/A
42 RB A/C Cut Control
43 WY Ignition Output (Power Transistor)
44 RL Check Connector
45 GB Check Connector
46 L Check Connector
47 R Trouble Code Output
48 W O(2) Sensor
49 W Fuel Injector #5, #6
50 W Fuel Injector #5, #6
51 WR Fuel Injector #1, #2
52 WR Fuel Injector #1, #2
53 WY Fuel Injector #3, #4
54 WY Fuel Injector #3, #4
55 B Fuel Pump Control
56 B Ground (Ignition)
57 B Ground (Ignition)
58 YR By-Pass Air Control
59 YL By-Pass Air Control
60 BR Ground (Fuel Injector)
61 BR Ground (Fuel Injector)
62 R Power (Fuel Injector)
63 Br Power Steering Control
ECU CONNECTOR PIN SPECIFICATIONS (XT & XT6)

ECU Terminal No. (Wire Color) Condition Volts or Ohms
2 (WHT) Ign. On 1-2V
3 (GRN/BLU) Ign. On (1) 0-10V
4 (YEL/BLU Or GRN/YEL) (2) Ign. Off Zero Ohm in "N"
6 (BLU/BLK) Ign. On (1) 0-10V
7 (RED) Ign. On 10-12V
8
XT (BLK) Ign. On (3) .1or4-5V
XT6 (GRN) Ign. On (3) .1or4-5V
9 (WHT/BLK) (2) Ign. Off 100-20,000 Ohms
10 (BRN/RED) (2) Ign. Off Zero Ohm
12
XT (WHT) Ign. On 10-12V
XT6 (RED) Ign. On 10-12V
17 (WHT) Ign. On (4) .1or4-5V
19 (BLK/WHT) Ign. On (5) 10-12V
20 (BRN/RED) (2) Ign. Off Zero Ohm
24
A/T (BLK/WHT) Ign. On (6) 10-12V
M/T (BLK/YEL) Ign. On (6) 10-12V
25 (BLU/WHT) (2)
Closed Throttle Ign. Off Zero Ohm
Open Throttle Ign. Off Infinity
27 (WHT/RED) Ign. On 10-12V
29 (YEL/RED) Eng. On (7) 1-3V
35 (WHT/RED) Ign. On 10-12V
36 (RED - XT6) (2) Ign. Off 532-588 K/Ohms
48 (WHT) Eng. On .1-1.0V
49 (WHT) (2) Ign. On 10-12V
50 (WHT) (2) Ign. On 10-12V
51 (2)
XT (WHT/BLU) Ign. On 10-12V
XT6 (WHT/RED) Ign. On 10-12V
52 (2)
XT (WHT/BLU) Ign. On 10-12V
XT6 (WHT/RED) Ign. On 10-12V
53 (WHT/YEL - XT6)(2) Ign. On 10-12V
54 (WHT/YEL - XT6)(2) Ign. On 10-12V
55
XT (WHT) Ign. On (1) 0-10V
XT6 (BLK) Ign. On (1) 0-10V
56 (BLK) (2) Ign. Off Zero Ohm
57 (BLK) (2) Ign. Off Zero Ohm
58 (YEL/RED - XT6) (2) Ign. On 10-12V
59 (2)
XT (GRN) Ign. On 10-12V
XT6 (YEL/BLU) Ign. On 10-12V
60 (BRN/RED) (2) Ign. Off Zero Ohm
61 (BRN/RED) (2) Ign. Off Zero Ohm
62 (RED) Ign. On 10-12V
(1) Fluctuates every 1.5 seconds while Green test connectors (in trunk) are joined together.
(2) ECU harness disconnected.
(3) Fluctuates 0-5 volts while cranking with starter.
(4) Fluctuates 0-5 volts while slowly turning crankshaft hub nut with wrench.
(5) With airflow meter disconnected.
(6) 10-12 volts with ignition in START position.
(7) Fluctuates around 2 volts while driving vehicle.
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