Unplugged ECU and found a single wire slipped in WITH/UNDER the biggest plug going to an unknown pin

[Gremo87]

I bought this car from a guy who'd only had it for a few months and didn't do any of the mods. It has DSMLink V3 lite - I was digging into the ECU to verify this.

So I unbolted it, and began unplugging it - when I got to the biggest yellow plug, I noticed a white wire coming from the same harness/batch of wires the plug was, but it wasn't actually connected to the plug - it had been flattened and part of the wires exposed and then slipped in underneath the plug so that, I'm assuming, the exposed wires were resting on one of the pins in the ECU's plug slot.....is this freakin' normal??

I dunno which pin it would've been going to. Attaching a picture.

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It was going in under the plug - on the side of the plug WITHOUT the clip that you have to press down to get the plug out. So I know what bank of pins it was going to, but not which exact pin - so I've left it disassembled until I hear from you fine folks.


On a side note - while we're here - the smallest yellow ECU plug has a black wire that doesn't go into the car's harness, but rather has had a thin orange wire connected to it which then goes to 2 unconnected ends - an orange and a purple. What might be the deal with that, if anyone knows - ? Pictures:

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[lasershark]

I'll take a bite. That wire could be a number of things depending on how your car is set up. Could be a sensor being logged (boost, wideband, ect...) You need to verify the pin the wire is going to or simply trace it. The orange wire is most likely ecmlinks "no lift to shift" wire.

 

[Gremo87]

It isn't going to a pin though. I mean it was, but I pulled the plug out and it was just shoved in there with the plug pressing it up against a pin - so when I unplugged it the wire came out too and now I don't know which pin it was on. :/ I thought it might have just been a wire that got stuck in there when the PO put the plug in...but when I pulled it out it was obvious that he'd flattened the wire insulation and exposed a bit of wire to contact whatever pin it was on.

I just tried to connect my laptop to the ECU with DSMLink and I get an error: "No response received"

Wondering if this white wire not being in there is what's causing this.....sigh.....no clue what to do. Was hoping to start learning how to tune today. Bahhhh.

PS. Thanks for chiming in!

 

[lasershark]

This link might help you out as to what pin the wire is from but you should try to trace it to see what it goes to.
https://www.ecmtuning.com/wiki/externalsensorinput

No lift to shift link
https://www.ecmtuning.com/wiki/clutchcutwire

And if you could update your profile so we know what you do or don't have on your car!

 

[Gremo87]

Ah I think you're spot on about the no shift wire. Looks just like that.

As for the other one, after looking at it some more, I don't even think it could have been in contact with any of the pins the way it was slid in there. If it was somehow, I would think it was pin 20 - on the list you linked that's the only one available to tap in to in the area that this wire was at. That would lock the car in Open Loop mode.....

It's coming out of the same taped up harness section that the rest of the wires that are actually connected to that plug come from....maybe I'll untape that later and see if I can figure out where that wire goes/comes from. Thanks for your help.

And

I'll have to work on getting my profile completed soon. I didn't do any of the mods and I have a very half-ass list of mods from the guy I bought it from. (he didn't know what all it had either - it has a lot. Pretty built.)

 

[Dsmkauai]

Do you have a wideband?

 

[Gremo87]

Do you have a wideband?

Yep.

And I just drove it for the first time after the wire thing - and it now wants to die when I push the clutch in to stop. It doesn't always die, but definitely starts bogging down. Died probably 5 times on a 15 minute drive across town. (on the way back I remembered to gas it a little each time )

Sooooo looks like that wire probably was connecting with pin 20 - locking the car in open loop. Because it never died like that before. Unless disconnecting and reconnecting the battery can reset something that might cause it to bog down and die like that...?

I dunno, I have a lot to learn and I jumped in the deep end with a built car. Bunch of stuff already done that I don't yet have the foundation to understand and/or tweak.

Regardless, it seems to me that I wouldn't want the car stuck in open loop mode, so that's just a bandaid - I need to figure out what's keeping my computer/software from connecting with the car and get the idle tuned better which should fix the dying issue -------- sound right?

 

[Dsmkauai]

It's for the wideband bro, pretty sure they tapped the wideband into the ecu and that's just the old wire for stock O2.

 

[miguelmcv]

There are only 4 white wires in that plug,. I think your loose wire is pin #2 which is white and is the Diagnosis/Data Data Transfer Select Manual.

I can see in the pic pin #22 (Top Dead Center Sensor) so descart that one, if you get a pic of the other side of the connector I can tell you for sure what pin it is...

 

[Gremo87]

It's for the wideband bro, pretty sure they tapped the wideband into the ecu and that's just the old wire for stock O2.

There are only 4 white wires in that plug,. I think your loose wire is pin #2 which is white and is the Diagnosis/Data Data Transfer Select Manual.

I can see in the pic pin #22 (Top Dead Center Sensor) so descart that one, if you get a pic of the other side of the connector I can tell you for sure what pin it is...

Wait I think there may be a misunderstanding. This lil white wire didn't come undone from the plug. It doesn't appear to have ever been a part of the plug. All 4 white wires in the plug are accounted for; this one is stray/additional. It does come out of the same batch of wires as the rest, but when I say it was plugged in with the plug I mean it was literally shoved in with the plug on the underside of it - not actually a part of the plug. (And all slots in the plug are taken)

I have the pin outs diagram and everything matches that - aside from this extra white wire which when pulled out results in the car wanting to die when pushing in the clutch....

Does that change anything?

Hope I'm understanding everything you're all saying.

And lastly - big thanks to everyone putting time in here. Much appreciated!!

 

[Dsmkauai]

Ya but in the first pic I can see the other end of that white wire spliced bro. If you have a wideband and logging it in ecmlink. The wire being cut and spliced was done to make that connection work. And you have the clutch cut wire and nlts wire hanging loose. Needs to be hooked up propelry bro, could be why your cars deing

 

[miguelmcv]

The wideband has nothing to do with the stalling easue, it's there just to calibrate the car but it doesn't interfere with the car unless is simulated from the O2 sensor...

To the OP
Take a pic of the wire where comes out of the plug or tell us what pin # is it so we can figure it out.

 

[Gremo87]

Ya but in the first pic I can see the other end of that white wire spliced bro. If you have a wideband and logging it in ecmlink. The wire being cut and spliced was done to make that connection work. And you have the clutch cut wire and nlts wire hanging loose. Needs to be hooked up propelry bro, could be why your cars deing

So you're saying the white wire in the foreground may be of no use now since the wideband might be what's spliced into that other white wire?
And yeah the wiring isn't the best - that's all from the previous owner. :/

The wideband has nothing to do with the stalling easue, it's there just to calibrate the car but it doesn't interfere with the car unless is simulated from the O2 sensor...

To the OP
Take a pic of the wire where comes out of the plug or tell us what pin # is it so we can figure it out.

Well, on the drive to work this morning I had no stalling issues........now I'm wondering if the wire has no connection to the stalling issue which might just be intermittent - I just got this car so I'm not completely familiar with it yet.

But - I'm not talking about the wire coming out of the plug. I'm talking about the wire in my hand in the pic. It doesn't come out of the plug, but comes from the same batch of wires that all of the wires in the plug do. So no pin number - it was stuffed in underneath the plug. I originally thought it was wedged in there too contact one of the pins, but I now have doubts about that - I don't see how it could have been touching a pin just shoved in underneath the plug like that. Ya follow? It's kinda hard to explain, maybe I'll take a pic of what it looked like before I pulled it.

 

[Dsmkauai]

^^ exactly how mine is bro for my wideband!! can you tell me which pin the tapped white wire in the first pic is? Again when your running a wideband and logging it. You would cut that wire and leave it. Then use the ecu side wire that's left and solder the widebands wire to it. Leaving the stock O2 sensor wire there alone unused. Not saying it is 100% but sure doesn't look and make sense.

 

[Gremo87]

Ahhhhh ok I gotcha now! That makes more sense - so the cut one must've just gotten stuck in with the plug on accident by whoever last plugged it in, and I wrongly assumed it was wedged in there contacting a pin. Ok so the stalling issue must just be an intermittent thing then. That makes me feel a little better - one thing less to figure out.

So I just need to get this stalling issue tuned out. I emailed ecmtuning last night to ask if there's a way I can confirm whether my cable is good or not, cause I just get the "no response received" error when I try to connect. Eager to get tunin'! Hoping it's something simple.

Thanks everyone, I think the wire issue has been solved.

 

[miguelmcv]

Well now to the not respond problem,,.

Turn off your laptop and connect to the car,, after connecting to the car start the car and leave it ON, then turn the laptop ON, pay attention to the ecmlink cable light (the square little box between the cable with a light in it), when turning the laptop ON the light will flash on intermittently, if it doesn't then the cable might be the easue but if it light up then cable is good, you have to look somewhere else.

Here is a good page to test and see if there is something wronge on the obd2 connector.

https://www.ecmtuning.com/wiki/connectionproblem

 

[Gremo87]

Doing it that way, the LED lights up once when the computer turns on, once again as Windows is loading, and that's it.
When I click connect, the LED blinks twice and then I get the error message.

Does that mean the cable is good? Or should it continue blinking once the computer is on?

 

[miguelmcv]

It means the cable is good, the signal goes to the OBD so you are good there, now you have to test the ports on the OBD side.

The link I posted tells you how to check the OBD outlet, fallow the instructions to verify the connector has signal.

The ECU can be checked by turning the switch to the off position, then turn it to the ON position (without cranking the engine), when you turn it to the ON position check the engine light, it has to be on for a couple of seconds and it turns off itself, if it stays ON or it doesn't turn ON at any time then the ECU could be your problem.

 

[Gremo87]

Ok pin 10's voltage checks out - it's about 4.7. (That's close enough to 4.5 right?)

Pin 1 checks out - it is pulsing.

I don't know how to check pin 12 for continuity to ground. I googled how to check continuity for ground and didn't find anything that seemed applicable here...any advice there?

I also made sure that each pin is seated firm and secure in the port - no loose pins.


The CEL comes on for a few seconds and goes off as it should.


So everything seems to be checking out fine....yet no connection.

Here's a picture of the fuse box by the diagnostic port - I don't know what these 2 red wires are for but thought I'd share in case it means something to you or anyone else.

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[miguelmcv]

When checking for continuity (ground) you have to use one end to ground and the other end to what ever pin you are testing, in this case pin #21, but you have to change the setting on the multimeter to continuity, here is a link to test continuity on a multimeter, read it so you get to know your tool and get an idea of what you are doing.

http://m.instructables.com/id/How-t...ep2/Getting-to-know-your-Multimeter-Settings/

 

[miguelmcv]

The red wires might be for a wideband or an extra assesory that you might have,.

What do you have extra?, wideband, turbo timer, etc etc etc., or just fallow the wires and see where they go to.

 

[Gremo87]

When checking for continuity (ground) you have to use one end to ground and the other end to what ever pin you are testing, in this case pin #21, but you have to change the setting on the multimeter to continuity, here is a link to test continuity on a multimeter, read it so you get to know your tool and get an idea of what you are doing.

http://m.instructables.com/id/How-t...ep2/Getting-to-know-your-Multimeter-Settings/

Ok I read the link (thank you!) and checked the pin - it's good. So all 3 pins tested have checked out fine. I emailed ECMTuning and Thomas Dorris replied that it sounds likely that it's a cable problem and suggested finding someone in my area with a known working cable to try with my car/laptop. So I'll try that next, unless you have any other suggestions - ?

Thanks a ton for your help Miguel, you've been great. Really appreciate it.

 

[miguelmcv]

Then now concerning about the cable, you are on you own, hope you find someone local to test the cable.

Glad to help out.