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XT & XT6

  1. ECU circuits are checked at the ECU connector with ignition in one or more of the following conditions; ignition switch off, ignition on and engine off, or with ignition on and engine running.
  2. To test pin voltage, carefully backprobe terminal at harness side of ECU connector. See Fig 1 and ECU CIRCUIT IDENTIFICATION tables below. Test each terminal between indicated terminal No. and body ground. Use wire color to help identify terminal. See WIRING COLOR CODE table.
  3. If specified resistance or voltage value is not found, test and repair, or replace circuit or affected component. Retest circuit to verify repair has been made. All tests are with ECU harness connected unless noted.
Fig 1: Identifying XT 1.8L & XT6 2.7L ECU Connector Terminals
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 ***** *****
12 W Air flow Meter (Power)
13 ***** *****
14 ***** *****
15 Lg Inhibitor Switch (AT)
16 BR Throttle Sensor (Ground)
17 W Crank Angle Sensor (Position Signal)
18 ***** *****
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 ***** *****
27 WR Control Unit Power (Input)
28 BY Specification Code
29 YR Car-Speed Sensor
30 BR Identification of AT and MT
31 ***** *****
32 Br Test Mode Connector
33 LgW Read-Memory Connector
34 ***** *****
35 WR Control Unit Power (Input)
36 ***** *****
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 ***** *****
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 O2 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 ***** *****
54 ***** *****
55 W Fuel Pump Control
56 B Ground (Ignition)
57 B Ground (Ignition)
58 ***** *****
59 G Auxiliary Air Valve Control
60 BR Ground (Fuel Injector)
61 BR Ground (Fuel Injector)
62 R Power (Fuel Injector)
63 ***** *****
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 ***** *****
12 W Air flow Meter (Power)
13 ***** *****
14 YW Inhibitor Switch (AT)
15 Lg Inhibitor Switch (AT)
16 BR Throttle Sensor (Ground)
17 W Crank Angle Sensor (Reference)
18 ***** *****
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 ***** *****
27 WR Control Unit Power (Input)
28 ***** *****
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 ***** *****
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 ***** *****
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 O2 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
XT & XT6 ECU PIN SPECIFICATIONS

ECU Terminal-Wire Color Condition Volts or Ohms
No. 2-White Ign. On 1-2 V
No. 3-Green/Blue Ign. On (2) 0-10 V
No. 4-Yellow/Blue or Green/Yellow (1) Ign. Off 0 Ohms in "N"
No. 6-Blue/Black Ign. On (2) 0-10 V
No. 7-Red Ign. On 10-12 V
No. 8
1.8L-Black Ign. On (3) .1 or 4-5 V
2.7L-Green Ign. On (3) .1 or 4-5 V
No. 9-White/Black (1) Ign. Off 100-20,000 Ohms
No. 10-Brown/Red (1) Ign. Off 0 Ohms
No. 12
1.8L-White Ign. On 10-12 V
2.7L-Red Ign. On 10-12 V
No. 17-White Ign. On (4) .1 or 4-5 V
No. 19-Black/White Ign. On (5) 10-12 V
No. 20-Brown/Red (1) Ign. Off 0 Ohms
No. 24
A/T-Black/White Ign. On (6) 10-12 V
M/T-Black/Yellow Ign. On (6) 10-12 V
No. 25-Blue/White (1)
Closed Throttle Ign. Off 0 Ohms
Open Throttle Ign. Off Infinity
No. 27-White/Red Ign. On 10-12 V
No. 29-Yellow/Red Eng. On (7) 1-3 V
No. 35-White/Red Ign. On 10-12 V
No. 36-Red (1) Ign. Off 532-588 k/ohms
No. 48-White Eng. On .1-1.0 V
No. 49-White (1) Ign. On 10-12 V
No. 50-White (1) Ign. On 10-12 V
No. 51 (1)
1.8L-White/Blue Ign. On 10-12 V
2.7L-White/Red Ign. On 10-12 V
No. 52 (1)
1.8L-White/Blue Ign. On 10-12 V
2.7L-White/Red Ign. On 10-12 V
No. 53-White/Yellow (1) Ign. On 10-12 V
No. 54-White/Yellow (1) Ign. On 10-12 V
No. 55-White Ign. On (2) 0-10 V
No. 56-Black (1) Ign. Off 0 Ohms
No. 57-Black (1) Ign. Off 0 Ohms
No. 58-Yellow/Red (1) Ign. On 10-12 V
No. 59-Yellow/Blue (1) Ign. On 10-12 V
No. 60-Brown/Red (1) Ign. Off 0 Ohms
No. 61-Brown/Red (1) Ign. Off 0 Ohms
No. 62-Red Ign. On 10-12 V
(1) ECU harness disconnected.
(2) Fluctuates every 1.5 seconds while Green Test Connectors (in trunk) are joined together.
(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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