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I think we cut one too many wires when stripping the harness. The end result is an ECU which seems to not be powering up, and therefore isn't running the fuel pump or anything.

Has anyone got a soft copy of the appropriate wiring diagram, or off hand know if there is a constant power wire going to the ECU?

I've got a wire going to the ignition circuit, and a big thick yellow wire going straight onto the +ve battery from the ignition relay, but I think the ECU needs some sort of power to it to actually be able to trip the ig. relay.

Also does anyone know of a way to test that the ECU is powering up? doesn't seem to be any lights inside it.

Have sent it to you in an e-mail paul .

Mike.

Symptoms:

1) Ignition relay not clicking when turn key to 'on'
2) EFI ( VL ) Fuel pump not getting power from ECU



I've got a thick yellow wire from the Ig relay to +ve through a 20A fuse. Test light shows power to at least this point.

I've got a wire going to Ignition power, Test light shows this gets power. Traced to wire into ECU and test light lights up there too.

I've got another wire going to the Starter +ve. ( can't remember if I tested that, will test tonight ).

The engine plugs are all plugged in, the Oil temp isn't, but the 02 sensor is.

I'm told this should be enough to start the engine, but it doesn't.


Any ideas ?

Perhaps this will shed some light.




Looks like there should be a yellow-red wire going from constant 12v. Fuse diagram shows it on a 10a fuse, so I should be able to use an inline fuse and dump it straight onto the +ve terminal.

Nope that wasn't it. I had that wire going into the ignition wires. I redid it into 12v constant and still no joy. :/

help!

Sending pm with details you need ( 95%sure anyway)

Fury came through with the win!

There was another wire ( Yellow with black stripe ) that needed to go into the Ignition circuit. Now I get the Ig and Fuel relays click ( fuel clicks probably twice a second, but I think it's supposed to do that? ) The EFI pump turns on.

I need to get some better clamps and fuel hose as there's a couple of leaks at the joins, so I haven't tried to turn the engine over too much yet.

I'll get better hoses/clamps tomorrow and see if I can get her started.

It's getting close!

Was the file I sent of any help.

Mike.

Paul, can you send me a copy of the pin out that you got. Will be kind of handy to have a look at it. I heard back from Al about it. Pretty much said exactly what you have already learnt.

Brett, If you want, I can do some of those as a quick reference, as far as pinouts , schematics and voltages and fault codes for ecu's - so they can be posted as downloads. Paul's was just a roughy, as I couldnt copy the files - had to scan hard coppies etc.

I have several models available ( not just Subies), so if you want...i can do a few that are popular, or send you the disk ( its only a demo for 14 days - installed yesterday) Cant say what it is, as it is heavily copywriten - and used by mechanical workshops.

I can PM you with details. I know you have the FSM's up there, but these are a simple reference..

I'm pleased that it was a help Paul

Chris

SUBARU IMPREZA 1.6L & 1.8L (EJ16 & EJ18 Engines) 1993 - 96 Engine Management Systems



Go To: INDEX Go To: COMPONENT LOCATION Copyright Ó Repco AUTO-TECH


Wiring Diagram

See Key to Wiring Diagram.





Key to Wiring Diagram

101 Battery 130 Air Conditioner Pressure Switch
102 Fuse SBF2 131 Air Conditioner Switch
103 Fuse SBF4 132 A/C Thermal Protector Switch
104 Ignition Switch 133 Air Conditioner Compressor
105 Fuse #16 134 A/C Evaporation Thermo Switch
106 Fuse #15 135 Diode
107 Inhibitor Switch (Auto) 136 Idle Air Control Valve
108 Fuse SBF5 137 Canister Purge Solenoid
109 Fuse #13 138 A/C Idle Up VSV Solenoid
110 Starter Motor 139 Relay - Main

111 Transmission Neutral Switch (Manual) 140 Relay - Fuel Pump
112 Instrument Cluster 141 Fuel Pump
113 Tachometer 142 Fuel Injectors
114 Malfunction Indicator Lamp 143 Oxygen Sensor - Heated
115 Vehicle Speed Sensor #2 144 Engine Coolant Temp. Sensor
116 Relay - Main Cooling Fan 145 Mass Air Flow Sensor
117 Main Cooling Fan Motor 146 Igniter
118 Sub Cooling Fan Motor 147 Ignition Coil
119 Diode 148 CO Resistor
120 Twin Diode 149 Throttle Position Sensor

121 Air Conditioning Relay Holder 150 Crank Angle Sensor
122 Fuse 20 Amp 151 Automatic Transmission ECM
123 Fuse 10 Amp (Automatic Vehicles Only)
124 Relay - Main Cooling Fan #2 152 Power Steering Pressure Switch
125 Relay - Sub Fan #1 153 Read Memory Connector
126 Relay - Sub Fan #2 154 Check Connector
127 Relay - Air Conditioner 155 Data Link Connector
128 Relay - Air Conditioner Cut Out 156 Test Mode Connector
129 Air Conditioner / Heater Fan Switch 157 Engine Management ECM


also this: http://lib.store.yahoo.net/lib/mroseusa/93ej18.gif

but colours seem to be a bit different.

and

ECM
The ECM is located under the Left Hand Side of the Dashboard.
It controls the EFI System and Ignition.
It also has a Fail Safe back up System.



ECM Voltage Table


Connector ‘A’
1 through13 top row
14 through 26 bottom row, when looking AT the PLUG clip at top



Pin # Circuit and Status......................................... Voltage

A1 Air Flow Sensor Ground
All Times........................................................ 0 Volts

A2 Idle Speed Controller
Engine Idling................................................... Voltage Pulses

A3 Engine RPM Output
Engine Idling................................................... Voltage Pulses

A4 Vehicle Speed Sensor
Ignition ON..................................................... 0 or 5 Volts
Front Wheels Turning...................................... 0 to 5 Volts Fluctuations

A5 Serial Data - Subaru Monitor
No Specifications Available.............................. N/A

A6 Serial Data - Subaru Monitor
No Specifications Available.............................. N/A

A7 Radiator Main Fan Relay #2 and Sub Fan Relay #2
Ignition ON
Relays Energized............................................ 0 Volts
Relays Not Energized...................................... Battery Volts

A8 Fuel Pump Relay
Ignition ON..................................................... 0 to 10 Volts Fluctuating

A9 Air Conditioning Cut Out Relay
Ignition ON
Relay Energized.............................................. 0 Volts

Relay Not Energized........................................ Battery Volts

A10 Power Supply
Ignition ON..................................................... Battery Volts

A11 Air Conditioning Switch
Ignition ON,
A/C Switch ON............................................... Battery Volts
A/C Switch OFF.............................................. 0 Volts

A12 Starter Switch

Engine Cranking.............................................. Battery Volts

A13 Power Supply
Ignition ON..................................................... Battery Volts

A14 System Ground
All Times........................................................ 0 Volts

A15 System Ground
All Times........................................................ 0 Volts

A16 Neutral Switch Manual Trans
Ignition ON
Transmission In Neutral................................... Battery Volts
Transmission In Gear....................................... 0 Volts

A17 Transmission Identification
Ignition ON
Automatic Transmission Fitted......................... 5 Volts
Manual Transmission Fitted............................. 0 Volts

A18 Self Cut-out
Ignition ON..................................................... Battery Volts

A19 Read Memory Connector
Ignition ON
Connected...................................................... 0 Volts
Disconnected.................................................. 5 Volts

A20 Test Mode Connector
Ignition ON
Connected...................................................... 0 Volts
Disconnected.................................................. 5 Volts

A22 Malfunction Indicator Lamp

Ignition ON
Light ON......................................................... <1 Volts
Light OFF....................................................... Battery Volts

A23 Radiator Main Fan Relay #1 and Sub Fan Relay #1
Ignition ON
Relays Energized............................................ 0 Volts
Relays Not Energized...................................... Battery Volts

A24 Air Cond. Load Signal Fast Idle Control

Engine Idling
Air Cond. ON.................................................. Battery Volts
Air Cond. OFF................................................ 0 Volts

A25 System Ground
All Times........................................................ 0 Volts

A26 Power Supply
Ignition ON..................................................... Battery Volts



Connector ‘B’

1 through 22, when looking AT the PLUG clip at top




Pin # Circuit and Status.......................................... Voltage
B1 Fuel Injector #2
Ignition ON...................................................... >10 Volts
Engine Idling................................................... Voltage Pulses

B2 Fuel Injector #1
Ignition ON...................................................... >10 Volts
Engine Idling................................................... Voltage Pulses

B3 Engine Coolant Temp Sensor

Engine Warm/Idling.......................................... 0.7 to 1.0 Volts

B4 Throttle Position Sensor Signal
Ignition ON
Throttle Fully Open.......................................... 4.5 Volts
Throttle Fully Closed........................................ 1.0 Volts

B5 Air Flow Meter Signal
Ignition ON...................................................... 0 to 0.3 Volts
Engine Idling................................................... 0.8 to 1.2 Volts

B6 Crank Angle Sensor Reference Signal
Ignition ON...................................................... 0 Volts
Engine Idling................................................... ±6 Volts AC

B7 Crank Angle Sensor Ground
Ignition ON...................................................... 0 Volts

B10 Oxygen Sensor Signal
Engine Idling................................................... 0 to 0.7 Volts Fluctuating

B11 System Ground

All Times........................................................ 0 Volts

B12 Fuel Injector #4
Ignition ON...................................................... >10 Volts
Engine Idling................................................... Voltage Pulses

B13 Fuel Injector #3
Ignition ON...................................................... >10 Volts
Engine Idling................................................... Voltage Pulses

B14 Power Steering Switch

Ignition ON
Steering Wheel Turned - Switch ON.................. 0 Volts
Steering Wheel at Rest - Switch OFF (no load).. 5 Volts

B15 Throttle Position Sensor Power
Ignition ON...................................................... 5 Volts

B17 CO Adjustment Signal
Coolant Temp 80°C
Vehicle driven for 1 Minute @ 24 kph
Engine speed to above 2,000 RPM, Idle Engine
Ignition OFF.................................................... 0 Volts

Ignition ON...................................................... 12 Volts For 1 Minute

B19 Purge Control Solenoid
Ignition ON
Solenoid Energized.......................................... 0 Volts
Solenoid Not Energized.................................... Battery Volts

B20 Ignition Control Cylinders 3 & 4
Ignition ON...................................................... 0 Volts
Engine Idling................................................... <3.4 Volts

B21 Ignition Control Cylinders 1 & 2
Ignition ON..................................................... 0 Volts
Engine Idling................................................... <3.4 Volts

B22 System Ground
All Times........................................................ 0 Volts

Fury and stinky you're legends, thats heaps easier to understand than the FSM pages I've got, I'm greatful to have them but they take some serious thinking to figure out.

So now for the real question, have you started it yet

Jordan.

No, I got home super late as I had an inner CV on the brumby pull itself apart.

Will get it started this weekend tho!