Wiring / Relay Issues. PLEASE HELP!

[Ju-STI-n-721]

So after having my car down for near two years I have finally got the thing together and technically running. The car started as near stock 1993 Eagle talon TSI. Over the last several months I have swapped a 6 bolt motor out of an early 1992 TSI (the seven bolt motor that was originally in the car had significant crank walk issues). The wiring harness that was originally in the 1993 Talon was very worn and brittle as well so along with the 6 bolt motor I swapped the main wiring harness from the 1992 in to the 1993.

The car currently starts right up but dumps fuel due to my upgrading the injectors. I am not able to connect to ECM link to adjust for this because I am having an electrical issue.

None of the interior lights come on, the windows do not work, the radio does not work, and the headlights / brake lights do not work.

The car does start however and the emergency flashers, turn signals, and windshield wipers do work.

My initial thought was that there was something not connecting properly to the MPI sensor, but if I am not mistaken the car would not even start without being able to communicate to the MPI sensor. Also I was thinking that one of the plugs that come into the car from the firewall on the passenger side car was not connected properly, this is not the case. I feel that some plug that I either mixed up or did not connect properly or an ungrounded wire is causing this. I have spent several several hours trying to track the issue down and have been unsuccessful.

I know that this is a rather vague question but can anyone PLEASE help point me in some direction to what plug, wire, sensor, or relay would be causing my interior electrical issue? I am running out of ideas here and have viewed the wiring diagrams for countless hours. Any advice or suggestion would help. Thanks!

 

[1990TSIAWDTALON]

It wouldn't start if it isn't talking to the ECU so that is good. The ECU isn't communicating with the OBDI port so that is what I would focus on.
I have a Factory Service Manual for a 1992 that should be in tomorrow, invaluable when it comes to things like this and can usually be had for around $30. I can glance through it and see if I can find the schematic for the ECU to the cabin as that is what is not working. Hopefully someone else will chime in with some suggestions also.

 

[Ju-STI-n-721]

Thank you so much for the response! I am going to work on the car with the multimeter all this evening and will concentrate more toward the obd side of the equation. Please let me know if you discover anything through your manual that could be helpful.

 

[Vegas Smith]

I would start by checking all your fuses near your left foot rest and replacing any that are broken or missing.

As for your connectivity issue, try different usb ports on your laptop. On mine, only one usb port connects properly. Good luck brosef.

 

[Biddy420]

Do the easy stuff first check fuses most obd ports run of the same fuse as cig lighter

 

[Ju-STI-n-721]

Thanks you so much for all of the responses. I generally try not to post a thread unless I really really need some help.


So far I have checked every fuse underneath the hood and on the left inner drivers side of the car. They all are good as far as my multimeter reads.

My interior is currently ripped apart and my next plan of attack is to recheck every plug and ground.

All advise helps. Thanks again!

 

[1990TSIAWDTALON]

Could be a bad ground. Easy test with jumper cables from the Neg side of the battery to the interior to a good piece of metal or a stud in the cab. A bad ground will make you pull your hair out for no reason.
Check for POWER at the fuses of course.

 

[Ju-STI-n-721]

I have tested / sanded / and verified that all engine bay and interior grounds are sufficient (put new connector rings on a few of them). Pulled and checked all fuses, swapped sensors and ECU's back and fourth and I still am having the same problem. The car will start right up but no windows, door locks, interior lights etc. Still not having any success. I am going to put a few more hours in the car this evening. All advise and suggestions help. Thanks.

 

[1990TSIAWDTALON]

Justin did you swap out the interior fuse box from the 92 to the 93? On my 98 TSI, I had some similar issues and the previous owner had put a 96 interior cabin unit in. I found a correct one and put it in and everything worked. Just thought I'd ask and throw that out there.
I should say also that you need to check for 12v on that bank of fuses. I'd bet it is non-existant on that row. A hacker could "make" it work if thats the case but I am OCD about hacking these cars anytime.

 

[19Eclipse90]

Fuse boxes are the same on '92-'94 models.

I do agree with Marty's point about the power there, though. Make sure that the 1-pin white w/ red tracer wire is plugged into the junction block at "A".

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[1990TSIAWDTALON]

I love the picture. I was actually in my new, today, FSM taking this picture for him. This is a 92 book.
Thanks for the clairification too!

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[boostdawd]

The fuse box on the driver side is also what I would recommend looking over. Make sure all the cables/plugs are connected. An fsm will help u greatly. From my experience it can be a bad switch/relay, fuse, or maybe even a wire that was cut. Did u make any modifications to the interior harness?

 

[Biddy420]

Make sure to check continuity I've had many wiring issues test good then found out through continuity test the wire is all corroded somewhere I didn't notice. Also look for burnt/melted wires normally when a wire shorts it leaves like a greenish powdery residue hard to miss when u know what ur looking for but testing the wires from one harness to the next will pin point any corroded wires sounds dumb but I can't tell u how many times I've had wires show correct voltage on a meter and then end up been toasted

 

[Ju-STI-n-721]

Good news! (well kind of good news)

Last evening I was able to get a hold of a couple local DSM buddies to swing over and help me diagnose the problem. One of them being Dr. Turbo (this guy really knows his 1gs):

http://www.dsmtuners.com/threads/who-is-dr-turbo.343343/

Long story short I was not getting adequate power from my positive terminal of the battery to the fuse box on the passenger side in the engine bay of the car. This was due to a loose and semi responsive connection on the power wire coming from the fuse box to the battery.

My taking from this:

A second or third pair of eyes always helps. I was going around chasing grounds and tearing my interior apart (and pulling my hair out) while the problem was right in front of my face. Also my friend's multimeter and electrical diagnosis tools were much better and more accurate than my inexpensive one. (they literally figured this out in a matter of minutes and I felt like quite the idiot). Good tools unlike some of the cheap ones I attempt to use are almost always worth the investment.

Contrarily after we got into ECM link, made some adjustments, and got the car running, it wanted to randomly shut off. It kept throwing the code 0023 for the cam angle position sensor.

Unfortunately I was experiencing this exact issue before I took the car apart a few years back. This was a big part of why I swapped the wiring harness with the motor. We used multiple CAS and MPI sensors from perfect running cars in attempting to troubleshoot this problem (I own a few extra sensors from old dsms). Still the same code was getting thrown every time causing the car to shut off.

We were leaning toward the conclusion that there is something not responding properly in the ECU. That is the only component that has not been replaced thus far that I believe could be causing this. Unfortunately I do not have access to another computer that is socketed otherwise I would just swap them and see if that fixes the problem.

So now I have contacted ECM Tuning and will be sending my epromed ECU along with an unsocketed ECU, the DSM link cable, and V3 chip into them for testing. I will be sure to post the findings!

Once again thank you so much for all of the help guys!

 

[lasthope05]

Resistance/voltage drops, with a DMM is the most important diagnosis skill to learn. You will learn how to fix 95% of electrical issues with this alone. The rest requires a scope.

 

[Ju-STI-n-721]

Just to let anyone who may be curious know, I did receive a response from ECMTuning this afternoon and there was an issue with my socketed ECU.

From testing they discovered that the IC4 chip inside the computer which is responsible for receiving the cam-sensor and crank-sensor signals was malfunctioning. Damage to the IC4 chip is usually caused by a wiring problem associated with the ignition system or by a failed component in the ignition system. Dave also said that it is possible that IC4 could have been damaged by a high voltage electrical discharge.

Hopefully my headaches are temporarily taken care of with the car and thanks to ECMTuning!

 

[Vegas Smith]

Word! Car looks awesome/ Create a profile for that thing

 

[KingKeith212]

i know this isnt really the same kind of question but when i bought my car there was no radio, so i bought the harness and wired the harness to the radio and nothing, having tried multiple different wire combinations im at a loss any help would be appericate

 

[smbgsx]

Anything I had to contribute has already been stated. this was an interesting read though. I feel your pain, sometimes the answer is right in front of you. usually the simple solution is the key. Then even when you solve one problem another problem jumps out at you and ruins the victory . keep it moving forward