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Home >> Subaru >> 1987 >> XT GL-10, 1.8 4, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> SPFI CEC System >> Trouble Shooting >> Trouble Codes
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Trouble Codes

To read trouble codes, observe oxygen sensor monitor light. This light has two duration periods of illumination, one period long (1.2 seconds) and one period short (.3 seconds). The long period signifies the tens digit in a numbered code. Short period signifies the ones digit. So for example: 3 long flashes and 5 short flashes, that would signify a code 35.

It is possible to have more than one code present. In this case, the lowest number trouble code should be diagnosed first, the next highest numbered code second and so on. Trouble codes will be repeated as long as the system is in that particular diagnostic mode.

Fig 1: System Layout
G61890
Fig 2: General Trouble Shooting Chart
G61891
NOTE: When using diagnostic charts, check the connector while it is connected unless specified otherwise. Be sure to check again from the beginning in order to prevent secondary trouble caused by repair work. When checking with vacuum hose disconnected from vacuum switch at E/G on, be sure to plug hose.
Fig 3: View Of Control Unit Connector
G201925Courtesy of SUBARU OF AMERICA, INC.
CONTROL UNIT TERMINAL IDENTIFICATION

Terminal Wire Color Description
1 LG Kick-Down Control
2 RL ECS Lamp
3 R Test 4
4 LR EGR Solenoid (Control)
5 GL Purge Control Solenoid
6 LY Air Conditioner Signal
7 N/A N/A
8 W Air Flow Meter Signal
9 B Air Flow Meter (Ground)
10 Y Line End Cord Output
11 L Line End Cord Output
12 RL Line End Cord Output
13 N/A N/A
14 YG Neutral Switch
15 YL Parking Switch (AT)
16 LgR Kick-Down Monitor
17 R Air Flow Meter Power (Output)
18 LgY Starter Switch
19 GB Crank Angle Sensor Power (Output)
20 GY Crank Angle Sensor Signal (Position)
21 BW Crank Angle Sensor Signal (Reference)
22 YG Car-Speed Sensor
23 WB Water Temperature Sensor
24 LG Idle Switch
25 W Throttle Sensor (Signal)
26 R Throttle Sensor Power (Output)
27 BW Power (Input)
28 GW Self-Shutoff Signal
29 W Power (Input)
30 BR Ground
31 Br Test Mode
32 RB AT/MT Identification
33 Lg 49 State/CA Identification
34 W O2 Sensor
35 B Ground
36 LW EGR Monitor
37 N/A N/A
38 RL Ignition Switch
39 LgW Read Memory
40 N/A N/A
41 W Power (Input)
42 BR Ground
43 RW Injector (+)
44 BR Ground
45 GR Air Control Valve
46 N/A N/A
47 LB Fuel Pump
48 RB Injector (-)
49 RL Power (Input)
50 N/A N/A
51 B Ground
52 WY Ignition Control