Think this will imply to some extent for your 2000 era Forester (may have OBD style plug too but not functional to OBD equipment):
Make sure your ignition is OFF Connect the Black ‘Read Memory’ connectors together as illustrated below.
When the above are connected you are in diagnostics mode. Turn your ignition ON and ‘read’ the ECU code(s) being reported according to the following instructions. Note, you may here relays clicking and your fan starting and stopping - this is normal when in diagnostics mode.
In Diagnostic Mode – No Fault is indicated by the Check Engine Light continuously & evenly flashing on/off (this is also used to indicate the successful completion of an ECU Reset).
Check Engine Light Pulse Width:
The long pulses (1.3 Seconds) indicate Tens and the short pulses (0.2 Seconds) indicate ones. Pulses are separated by Short Pauses (0.2 Seconds), multiple codes are separated by a Long Pause (1.8 Seconds).
The simplest way for an inexperienced mechanic to retrieve codes is to write the codes down in a sort of Morse Code (dots and dashes), and start a new line when you get a 1.8 Second pause (for NEW code), and then add the actual numbers up after code retrieval is completed.
(See Example Below)
--- CODE EXAMPLE, SINGLE CODE ---
1.3 second pulse (10)
0.2 second pause
1.3 second pulse (10….for a total of 20)
0.2 second pause
0.2 second pulse (1…..for a total of 21)
0.2 second pause
0.2 second pulse (1…..for a total of 22)
0.2 second pause
0.2 second pulse (1…..for a total of 23)
(Code 23 — MAF Sensor)
--- CODE EXAMPLE, MULTIPLE CODE ---
1.3 second pulse (10)
0.2 second pause
1.3 second pulse (10….for a total of 20)
0.2 second pause
0.2 second pulse (1…..for a total of 21)
0.2 second pause
0.2 second pulse (1…..for a total of 22)
0.2 second pause
0.2 second pulse (1…..for a total of 23)
1.8 second pause (this means NEW code)
1.3 second pulse (10)
0.2 second pause
0.2 second pulse (1…..for a total of 11)
0.2 second pause
.2 second pulse (1…..for a total of 12)
(Codes 23 and 12, MAF Sensor and Starter Circuit)
How to clear them!
1. Ensure engine is at normal operating temperature, turn engine off
2. Locate the two ECU connectors, located under the steering column and consist of a black plastic male and female connector, and a green male female connector
3. With the ignition OFF connect black to black and green to green.
4.Turn on ignition, do not start the engine, depress the accelerator pedal to full throttle, then return it to the half-throttle position and hold for a few seconds, and then release
5. Engine Check lamp turns on
6. Start engine and then drive for at least one minute, keeping road speed above 10mph.
7. ECU is now re-set.
8. At this point the check engine light should start to flash the all clear signal (steady 1/2 second interval flashes). If the check engine light does not flash, or indicates some other sequence, there is a fault present in the system, and should be professionally checked for necessary repairs.
9. Stop the car and turn off the engine.
10. Disconnect the black and green connectors.
11. Job complete
Error codes >>>
1 Engine Speed Signal Circuit
11 Crankshaft Position Sensor
12 Starter Signal
13 Camshaft Position Sensor
14 Fuel Injector No. 1 (Legacy, Impreza, Justy, SVX)
15 Fuel Injector No. 2 (Legacy, Impreza, Justy, SVX)
16 Fuel Injector No. 3 (Legacy, Impreza, Justy, SVX)
17 Fuel Injector No. 4 (Legacy, Impreza, SVX)
18 Fuel Injector No. 5 (SVX)
19 Fuel Injector No. 6 (SVX)
21 Engine Coolant Temperature Sensor
22 Knock Sensor
23 Mass Air Flow Sensor Circuit
24 Idle Control System Malfunction
24 ISC Valve (Stick)
24 Open/Short in ISC Valve Circuit
26 Intake Air Temperature Sensor
27 ATF Temperature Sensor Circuit
28 Knock Sensor #2
29 Crankshaft Position Sensor 2
31 Throttle Position Sensor Circuit
32 A/F Sensor #1 System
32 A/F Sensor #2 System
32 Oxygen Sensor
33 Vehicle Speed Sensor
35 CPC System
36 Turbine Speed Signal
37 Rear O2 Sensor Circuit / A/F Sensor Circuit Malfunction
38 Torque Control Signal #1
38 Torque Control Signal #2
38 Torque Control Signal System
38 Torque Permission Signal
39 Traction Control System
41 Air/Fuel Adaptive Control
42 Idle Switch
43 Accelerator Pedal Switch
44 Turbocharging Pressure Control Signal
45 Pressure Sensor
46 Neutral or Parking Switch or Circuit
47 Fuel Injector
48 Lean Burn System
49 CO Resistor
51 Neutral Position Switch
52 Parking Brake Switch (Exc. Justy)
53 Antenna
53 Anti-Quick Operation Mode
53 Communication Error (Time Over)
53 EGI Control Module EEPROM
53 IMM Circuit Failure (Except Antenna Circuit)
53 IMM Control Module EEPROM
53 Key Communication Failure
53 Reference Code Incompatibility
53 Use of Unregistered Key
54 Air Intake System
55 EGR Valve Lift Sensor
56 EGR System
57 Canister Control System
58 Air Control System
61 Air Suction Control Solenoid Valve
62 Exhaust Manifold Valve Negative Pressure Control Solenoid
64 Relief Valve Control Solenoid Valve 1
64 Relief Valve Control Solenoid Valve 2
65 Differential Pressure Sensor
66 Twin Turbocharger System(H)
66 Twin Turbocharger System(S)
66 Twin Turbocharger System(T)
66 Two Stage Twin Turbocharger System
67 Exhaust Manifold Valve Positive Pressure Control Solenoid
68 Turbocharging Pressure Control Output Signal #2
71 Shift Solenoid Valve
72 Shift Solenoid #2 Circuit
73 Low Clutch Timing Solenoid Circuit
74 Brake Clutch Timing Solenoid Circuit Malfunction
75 Line Pressure Duty Solenoid Circuit
76 Brake Clutch Pressure Duty Solenoid Circuit Malfunction
77 Lock-Up Duty Solenoid Circuit
78 Tiptronic Solenoid System
79 Transfer Clutch Duty Solenoid Circuit
81 Torque Up Control Valve
85 Charger System Circuit Malfunction
86 CAN (Communication System)
87 Variable Induction Solenoid Valve Circuit Malfunction
88 Fuel Pump Circuit Malfunction
89 VVT Systems (L)
89 VVT Systems ®
91 TCS Relief Valve
92 Electrical Generation Control Signal Circuit Malfunction
93 Vehicle Speed Sensor #1 Circuit
94 Lateral G Sensor Signal Circuit Malfunction