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Expansion harness wiring help needed


SLOW240

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Hey new here, I've got a Link PNP I'm wiring into an S14 Silvia with a built SR20 and I can't find proper info on wiring my sensors in. I'll copy and paste my email to my dealer here, I have not heard back from them yet:

I have an oil pressure sensor, Fuel pressure sensor, and IAT sensor, as well as the CAN Lambda sensor. My drawing from a year ago shows 

S Ground - shared by FP, and OP sensor
+5V - shared by FP, OP and IAT sensors 
Volt 5 - oil pressure
Volt 6 - Fuel pressure
Temp 3 - From IAT

-Does this look about right?
-Am I okay the wire all 3 sensors to the same 5V in parallel?
-Am I okay to use the same Ground wire to all 3 sensors in parallel?
-I have to check the manuals, it probably would answer my question but I want 5v to IAT and then the other side to Temp 3 right?
 
And Could you show or explain the proper way I should be wiring in a terminating resistor into my CAN Lambda circuit?
 
So that was the email. Now after reading in the link software I see I'm wrong on the IAT sensor and need to wire it to Temp 3 and ground correct? I'm having a really hard time finding any definite information on the actual wiring of sensors. I live quite far up north and just towing it to the tuner and letting them deal with it is not a viable option so I've gotta figure this out.
 
Edit, I'll add some photos as well, I don't see 2 volt inputs on the board like in the diagram so that's got me a little confused 

Screenshot_20230209_223044_Opera GX.jpg

Screenshot_20230209_212235_Gallery.jpg

20230216_193351.jpg

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Fuel Pressure takes 5V, Signal ground and An Volt

Oil Pressure takes 5V, Signal ground and An Volt

IAT takes Signal ground and An Temp

CAN Lambda most likely doesn't need a terminating resistor if it is the only other item on the CAN bus. Terminating resistor goes between the CAN High and CAN Low (White and Green wires) near the CAN Lambda plug.

 

37 minutes ago, SLOW240 said:

Screenshot_20230209_223044_Opera GX.jpg

This image is from a GTR plugin not an S14 plugin, all plugins have different expansion plug setups

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Okay thanks for that help, now looking at the photo of mine, it only has one Volt input that I see, am I missing something here? Where can I wire my fuel and oil inputs to?

Am I okay to wire 3 sensors to the signal ground in parallel, and 2 sensors to 5v+ in parallel?

Found this photo online that may be more accurate? But it's only confused me further as I don't have any pins that don't seem to be able to accept an input. Unless this is S13 only as it says CA in the header

Screenshot_20230216_202031_Opera GX.jpg

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Signal ground and 5V can be split and fed to multiple sensors with no issues.

From the picture of your ECU it looks like you have the Long Header S13/S14 plugin, the second expansion header has a heap more analogs or alternatively you could reuse your AFM (An Volt 4), Narrowband O2 (An Volt 1) or factory MAP sensor (An Volt 2) wire for one of your pressure sensors.

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So the only way to run 2 pressure sensors is going to be to get a second expansion harness to use the other plug in as well? Is there any other input in the one shown I can use for the second sensor or am I outta luck there? I really don't want to buy and install a second harness for 1 wire. I'm not seeing where these AN 1, 2 and 4 inputs are, unless it's on the other plug. I didn't take a photo far enough away to see the other plug.

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1 minute ago, SLOW240 said:

So the only way to run 2 pressure sensors is going to be to get a second expansion harness to use the other plug in as well?

Or to use some of the unused wires from the factory wiring harness as stated above.

 

2 minutes ago, SLOW240 said:

I'm not seeing where these AN 1, 2 and 4 inputs are, unless it's on the other plug. I didn't take a photo far enough away to see the other plug.

Main header plug

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Ah I gotcha now. I didn't realize I could do that, I'll have to look up a connector pinout and see which ones can be used without causing further issues haha. Hacking into the factory harness worries me, but I'll do my research and see where I can pin it to in order to get a reading. Do you have any pointers on that? Not sure how versed you are in S Chassis specific stuff but any pointers would be appreciated .

 

Edit: a quick Google search is showing me I can use AN 4 from the MAF plug or AN 1 from the 02 sensor plug. I'll try to figure out which wires these are at the engine bay plug side, should make it easier than running a wire back to the ecu.

Edit 2: I've found the pinout for my ecu in PClink, this should make it far less confusing. I'll double check continuity to make sure I have the right wires but looks like ill be able to use AN Volt 2 fairly easily.

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