ECU Harness, red/white wire goes where? Options

[6gsillyca]

So I pulled my ECU yesterday, and in the process I accidentally pulled one of the pins out...

Hoping one of the wiring guru's can help me out and tell me where this belongs.

[lagos]

Super easy fix.
See the white rectangle thing in the center of of that plug in the pic? Get a small flat head screw driver or a knife and use it to pry that up. That is what locks/unlocks the pins. Then when you unlock it, slide the pin back in until it clicks and push that tab back to lock the pins in place.

[korban]

Looks like your wirings been spliced already. What engine do you have? Car year?

Judging from the way that wire is taped in the harness it came from the middle plug, can you show me a picture of the wire side of that plug?

[6gsillyca]

Thanks Lagos. Is that how I would go about re-pinning the harness aswell?

Do you know where the red/white plug is supposed to go? I will try and grab a wire side pic.

93 JDM 3sgte, 98GT USDM droptop.


Also, I have done some reading on mr2oc, and need a little bit of verification. I understand that 93jdm harness is plug and play with 93jdm ecu and 93-95 usdm ecu. 93 jdm ecu p/n of 17380.

I currently have 2 ecu's (one came with car, and second I picked up off mr2oc). The one that came with the car, is a 17321, which I understand is a jdm ecu from 90-91. I was told this ecu may have been chipped (blitz, mines etc) as it came with 550 installed on the clip. This ran the car fine, except I wanted to put stock 440's back, in an attempt to try and regain some mileage.

I put some 440's in aswell as a 17331 ecu, and the car seems to run the same. Still getting about the same mileage with the 440's and the (17331) ecu. Now the 17331 ecu is from a 91T USDM.

Why do both ecu's run my car? Most people that have 93jdm harness/90-92 usdm ecu are unable to get it to crank, which makes me think that I might not have a 93jdm harness, but possibly ~91. The fact that the ecu that came with the car, only being a 91-92jdm ecu, also makes me think this.

[lagos]

Thanks Lagos. Is that how I would go about re-pinning the harness aswell?

Yes, however some plugs (like the ecu plugs) have a different way of unlocking.
ECU plugs unlock like this..


Also, once you unlock it, you have to use a pin or needle to pry up on the pins inside the plug to pull them out.

I currently have 2 ecu's (one came with car, and second I picked up off mr2oc). The one that came with the car, is a 17321, which I understand is a jdm ecu from 90-91. I was told this ecu may have been chipped (blitz, mines etc) as it came with 550 installed on the clip. This ran the car fine, except I wanted to put stock 440's back, in an attempt to try and regain some mileage.

If you unscrew the top cover of the ecu, you should be able to tell if there is a Techtom board installed in it or not.

I didn't check your part numbers, but a 90 ecu/harness should not be able to run in a 93 ecu/harness without being repined. Here are the differences between the two harnesses. I made this little chart when I converted my harness to run a 93 SARD ecu.

[korban]

If it's the same as some wiring i've done, there are 2 red/white wires in the large plug, Injector 1 and the power for the oxygen sensor heater.

Also in the middle plug there is a red/white for a diagnostics line to the 'check' connector. The air temp wire might be red/white too, but I was using an aftermarket one.

Does your car run? If you haven't tried, don't until you post a wireside pic. If you have do you have any error codes or lights on your dash?

[6gsillyca]

I took the cover of the ecu off, but I do not know how to tell if it has a techtom board installed... There is a big circut board with "3sgte, 0129 93.4.4" written on a piece of tape on the underside, connected to another circut board built in the ecu housing.

I know that the 2 ecu's should not be able to run a certain harness, so that makes me wonder which harness I actually have...

[lagos]

Take pics of it and post them up. I can tell you if it has the techtom board in it or not.

[6gsillyca]

I will try and grab some pics of the wire side of the harness, but here is my ecu in question

[lagos]

hmm, wtf is that! lol
Thats not a techtom board, and at the same time that doesn't seem to be stock.

[6gsillyca]

lol that makes me wonder even more what sort of harness/wiring/ecu I have in my car...

That ecu had 17321 on the back, and should be from a 91jdm sw20...

This post has been edited by 6gsillyca: Feb 20, 2009 - 10:36 PM

[lagos]

Post some pics of that on mr2oc and see if the ats guys can tell you what it is. I know 93s did come with two boards in them, but that hot glue gun job doesn't look factory.

[6gsillyca]

I did not think that the hot glue, nor the masking tape are oem.

[6gsillyca]

Looking to get her back together next week, so hopefully I can figure this wire out.

BTW for those interested, it turns out the secondary board is some sort of FCD hardwired into the ecu.

[enderswift]

fcd?

[6gsillyca]

If someone could help me figure out what year harness this is, that would be greatly appreciated. It seems to match up closest to a 91 usdm sw20...

fuel cut defencer. not 100% sure how that one works, but they generally raise the stock fuel cut, allowing you to boost more.


This post has been edited by 6gsillyca: Jun 13, 2009 - 12:04 PM