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2.5S to 2.5SL interior wiring harness swap

3213 Views 158 Replies 5 Participants Last post by  markismail
Does anyone know if I would be able to swap the wiring harness for my 2.5S with a harness from a 2.5SL or even a 3.5SL to incorporate the use of the heated seats, and steering wheel controls, and any other features?

I'm not sure exactly which wiring harness I would have to purchase but I already have my hands on the harness for the heated seats and have my eyes on the steering wheel with volume controls. I'm just not sure what harnesses i would need or if I need to swap out the fuse box for the heated / power seats also.
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It isn't one harness. For the seats it's three, Main, Body, and Engine Room. For the steering controls it's just Main, but you'll need a different head unit and possibly a new spiral cable. Be advised that the console and dashpad both need to be removed to replace the Main Harness. It isn't a small job.
Alright, I have this new head unit already that part is done haha. Do you know the part numbers that would be needed? I found a wire harness with part # 240112B00 but I'm not sure if that's it. Would the BCM need to be switched also? If all of that is needed just for heated seats i'll probably sit out on that for now but I would at least like to know what the part number is for the main harness for the steering controls
You're probably better off with aftermarket for the seat-heat anyway. The problem with the harnesses is that Nissan doesn't specify which harnesses fit which equipment. It's likely that your only hope is to find a model with the equipment you want in the JY and get the number off the harness tag.
Okay I see i'll have to check it out, I thought there would be a way to know which harness it was that connected from the steering column to the radio Thank you though!
Do you know one of the part numbers just so I can get an idea of what to look for? I'm not sure which ones I should even look at
Mains all have a 24010 prefix. Engine Harnesses are 24011, Engine Room Harnesses are 24012. Body Harnesses are usually 24014, but there's often more than one along with various sub-harnesses.
Okay I'm going to try this out i should be able to pick one up for a couple of bucks. I'll report back when it's all complete :)
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Hey guys so I’m taking the harness apart and I’ve found this brown connector with a pink and red wire that is not on my harness. Any idea what this connector is for?
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Given the location and color, I'd say it's probably for a tweeter speaker at the corner of the dash. If so, you should find one just like it at the other end.
That’s what i originally thought as well but this one seems to be going towards the bottom right near the ECU and i have a tweeter already wired with a black and white wire on the top. Maybe it’s for a second tweeter? Also any idea how to remove this cabin air intake assembly? Haha
Exactly where does it position when the harness is in place? Could be a glove box lamp or could be a sensor for the HVAC.
Alright i finished the install and i have two wires that aren’t matching on the original harness. This is where the brown connector lays around and it doesn’t have much length to move from that location in this picture
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I’m not sure if it’s for the night time running lights or not because I’m pretty sure it’s supposed to be on the other side but that side still only has one connector for the security light.

For the second connector that’s not matching it’s a 3rd connector for the thermostat controls

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Now my question is will i have to change the ECU now?
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What year is the car, I'll pull up the harness diagram and see what I can find out.
I appreciate that a lot! It’s a 2005 2.5S and the harness *should * be a 2005 2.5SL
If that's for the HVAC controls, then the harness must be for Auto A/C. You might need to change the whole HVAC.
Oh wow i didn’t know there was different HVACs I’ll look into this now thanks
I did some research and figured out the third connector for the AC controls was actually the light for the air bag light. I actually was able to confirm it with the light I had from a previous part buy I did on an SER too bad I need to get another ac cover now. Maybe I'm missing something with the connector and will realize it when I actually re-install the dash after I change this heater core Thanks for the help! Where did you get the schematic from?

Also I'm a little confused with the steering wheel controls. The harness I had only had two connectors for the radio. Isn't there supposed the be three for the new harness with the controls?
Alright now I know i've seen this harness before for the audio connectors by metra but is there a connector harness for the steering wheel controls connector? I'm trying to use the axess SWC-1 and in the docs it's saying I need to tap into the 16 pin connector harness but I can't seem to find a harness for that connector so I don't have to tap into the factory wiring. All the harnesses I come across are only for the 2 front and rear speakers from what I can tell but I know there is a third one if anyone knows where I can purchase one that'd be great!
So this is where I’m at. I’ve been sick this whole week so not much was done but i have two new wires with this new harness that I’m not sure what they do. One still being that brown connector near the ECM and this white / yellow connector that seems to to the same way as the HVAC wire
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Ive also noticed that the wiring that goes to the driver side a pillar is different because the base model Altima has no Sun roof i assume.

I’m however going to try and wire up the heated seats into the car since I’m already trying to add in power the driver seat and was curious which wire is the trigger for the heated seats on the switches so i can wire them into a relay. I’m pretty sure it’s the grey / blue and grey / red wires that i can use as the trigger but wanted a second opinion
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The White/Yellow is probably for the trunk release Valet Switch in the glove box. For the heated seats, you need to use a DPDT switch (or two SPDT relays) and not a single relay. To get high-low, the seat heater elements get their 12V power in parallel for high, in series for low. Hit the "Seat" section of the SM for how they wire up, page SE-13.
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I didn't realize there was a high and low setting but I'm going to just wire up the high setting and call it done since I don't feel like running all that extra wiring since it won't really be used that often. but thanks for the heads up. and now I'm going to be using the red / grey wire on left and blue / grey on the passenger side
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Yep, for high-only you want ground to 1 and 3 and power on 2 for each seat.
So I tested the harness out and this harness isn’t sending power to the switches so I’m just not gonna attempt to add heated seats because of the amount of wiring that’d be involved. However i did get my entire dash back together now but unfortunately have an airbag code b1054/b1049 and no horn which means i need to replace this clock spring as well i assume.
Yep. Those are both driver's bag codes, so a mismatched clockspring is a good assumption.
Is there a specific one that I have to swap out? Like a difference between 2.5s and 2.5SL? I think there are multiple clock springs from different makes that would fit so I'm not sure
If you can get the VIN for the harness donor, that's the easiest way to get the right part. If you can't then it's a guessing game.
Going to get the same clock spring from the donor by next week so everything should match up then hopefully. I just noticed that the radio is not getting any power from either the ignition or battery could that be a different issue or is there something else related to the harness?
Going to get the same clock spring from the donor by next week so everything should match up then hopefully. I just noticed that the radio is not getting any power from either the ignition or battery could that be a different issue or is there something else related to the harness?
Never mind was the 15amp fuse under the hood thankfully 😅
For the steering controls it's just Main, but you'll need a different head unit and possibly a new spiral cable.
I just got the new spiral cable and going to install it in the morning and hopefully, all of that works out Now I have no power to the passenger window 🙃 Nissan somehow managed to use the same body harness connectors for the front door harness but different wiring configuration for the switches. I'm going to look into maybe being able to re-pin the current connector in the same configuration that the switches call for and hope for the best. Trouble now is figuring out what wires to change for the new switch
It's probably the wrong switch. Chances are an SL had full Auto on both front windows, an S would probably have it for driver only. With Auto on the passenger side, there's a LAN link between the two switches. You probably won't get it to work right without changing out the passenger switch, and maybe the Master switch as well.
I'll get some pics tomorrow, The S switch with only driver auto fit but didn't allow me to lower the passenger at all or lock the doors and now the SL switch I got from the donor won't fit into the door harness. I just can't believe that there are this many differences that I didn't account for but I'll get it figured out.
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