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Discussion Starter · #1 ·
I just wrapped up my auto to manual swap on my 2000 2.5 and it went really smooth until I got to solving the NPS CEL and hooking up the starter interlock/clutch switch. I found lots of written instructions that all seemed very vague on how to set up the circuit and not enough info for me to actually do it. After some digging through the FSM, I found 3 diagrams that had everything I needed. I combined the 3 into one easy to read wiring diagram below.

The first diagram below shows how this circuit comes from the factory including the relay you will have to add. Some models have a 12v output from the ECU pin, but my model had 5V signal (check your own circuit). I didnt have a normally open 5v relay and didnt feel like finding one so I made and used the second diagram. This is a slightly altered circuit but retains the same functionality without the relay.

The white/black labeled wire coming out of the ecu and the white/red wire going to the starter circuit are the two wires (next to the reverse light pins) from the old gray auto trans plug that you can jump together to start the car. They are either pins 9 and 10 or 11 and 12, I cant remember off the top of my head atm. If you wire this all up it should resolve your NPS CEL and prevent you from starting the car unless you have the clutch in and car out of gear. I am 500mi into my swap and havent had any CELs pop up. Good luck!

NOTE: Grab a multimeter and check for continuity and voltage before doing any of this to verify the wire you are using is in fact the one you think it is. Im not responsible for any mistakes or damage done to yourself or car.

Stock wiring
86748


Altered wiring without relay
86749
 

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Discussion Starter · #2 ·
I need to make a correction. I was probing around my starter wiring the other day and I discovered something. So I mentioned that you needed a 5V relay instead of a 12V because I was reading 5V off of the WB (B135 26) wire. When I was initially testing, I failed to check the wires voltage when the car was cranking. I found that the WB wire is 5V with accessory on, but it does actually provide 12V when you are turning the key and attempting to crank the starter. Im going to try and get a relay added into the circuit and Ill update on anything I find.
 

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just came across your post after doing a manual swap in my own car.

I was looking at your diagrams here they don't make that much sense because there missing a lot. if you wire pins 3 and 4 from the realy to pin 12 on the inhibitor switch harness, pin 1 on the relay to pin 11 on the inhibitor harness and then finally pin 2 on the relay to one of the wires on the clutch switch harness( other pin on clutch harness to ground)you'd be good to go.
By the way this is with a factory starter relay and harness.

unless im missing something... this is how I did it and everything functions 100%.

the information out there is not vague if you look at the wiring diagrams out there. Your post causes more un necessary confusion to fellow swappers as it doesn't quite look like you fully understand how to read the diagrams if you never could figure it out. If you need help with something PM me
 

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Discussion Starter · #4 ·
Hey infiniah, thanks for the reply. What I have posted to date is how I wired my system and it's been fully functional for about 5-6 months now. I'd be happy to double check my work, it's always possible I fat fingered something, I'll have to check during the week. I do have am undergrad and masters in electronic/electrical engineering so I'm more than proficient in reading diagrams, but I appreciate you reaching out for assistance. I'll take a second look in the next week or two and try to confirm what you are saying in your reply.
just came across your post after doing a manual swap in my own car.

I was looking at your diagrams here they don't make that much sense because there missing a lot. if you wire pins 3 and 4 from the realy to pin 12 on the inhibitor switch harness, pin 1 on the relay to pin 11 on the inhibitor harness and then finally pin 2 on the relay to one of the wires on the clutch switch harness( other pin on clutch harness to ground)you'd be good to go.
By the way this is with a factory starter relay and harness.

unless im missing something... this is how I did it and everything functions 100%.

the information out there is not vague if you look at the wiring diagrams out there. Your post causes more un necessary confusion to fellow swappers as it doesn't quite look like you fully understand how to read the diagrams if you never could figure it out. If you need help with something PM me
 

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Discussion Starter · #5 ·
just came across your post after doing a manual swap in my own car.

I was looking at your diagrams here they don't make that much sense because there missing a lot. if you wire pins 3 and 4 from the realy to pin 12 on the inhibitor switch harness, pin 1 on the relay to pin 11 on the inhibitor harness and then finally pin 2 on the relay to one of the wires on the clutch switch harness( other pin on clutch harness to ground)you'd be good to go.
By the way this is with a factory starter relay and harness.

unless im missing something... this is how I did it and everything functions 100%.

the information out there is not vague if you look at the wiring diagrams out there. Your post causes more un necessary confusion to fellow swappers as it doesn't quite look like you fully understand how to read the diagrams if you never could figure it out. If you need help with something PM me
Actually, i just took a quick look and from what I can tell, you described the exact same circuit I have listed in the diagram. You just swapped the poles from me in the energizing circuit and the N/O (output) poles on the relay. Your 2 is my 3 and your 1 is my 4 etc. Should functionally be identical.
 
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