damn this wire! (HELP!)

[jetjock]

A little electrical humor there.

First off, if you're not sure of where something goes use a fused jumper to connect it. One of those cheap inline fuseholders with a 10 amp fuse in it will do. That way the only damage will be a blown fuse. Second, all the hot wires in the car come from the battery positive. If you know the wire is already hot connecting it there won't cause anything to happen. It's the same point electrically. Lastly, the wire you've been puzzled about looks to be your Alternator B+ line. That's why I said not to ground it. Easy enough to tell just by looking at the alternator...

 

[Tae361]

A little electrical humor there.

First off, if you're not sure of where something goes use a fused jumper to connect it. One of those cheap inline fuseholders with a 10 amp fuse in it will do. That way the only damage will be a blown fuse. Second, all the hot wires in the car come from the battery positive. If you know the wire is already hot connecting it there won't cause anything to happen. It's the same point electrically. Lastly, the wire you've been puzzled about looks to be your Alternator B+ line. That's why I said not to ground it. Easy enough to tell just by looking at the alternator...

well by unbundling the wires it did go through the fuse box and eventually split into two wires going into the alternator..

however i already have a wire coming from the top of the alternator to the positive battery terminal, its a black and yellow wire. if the current setup is correct with the black/yellow wire coming from the alternator to the positive battery and the wire that i have free is live from being in circuit already, where does it go?

 

[jetjock]

Than it must be the alternator sense line. Connect it to battery positive and move on...

 

[Tae361]

Than it must be the alternator sense line. Connect it to battery positive and move on...

i understand now, i'm just trying to figure out which is the start of current flow in the circuit, it would be the alternator sense line, to the alternator, and the bigger line from the alternator distributing to the battery?

also hypothetically speaking, without having the alternator in line properly, would that even effect the iginition/no spark problem. mostly because it should spark as long as the battery has sufficient voltage? or is this wire not being connected cutting the ignition system out of the circuit entirely?

if the circuit flow goes from the alternator to the fusible link to the battery it would make sense... since there will be no voltage through the other white wire connected in tandem on the fusible link.

my mind is exploding!

 

[suprabad]

is this the white wire that i've encountered that needs to be connected to the + side of the battery, it would explain why the ignition isn't working

the white wire being the one connected to the battery through that symbol in which i dont know what it means...

First off, the white wire is connected to the black B2 wire via a fusible link (the symbol that you didn't know what it meant). The symbol looks like a long streched out S.

Is your battery at full charge?
As I recall (and someone will surely correct me if I'm wrong), the ECM will not let the ignitor fire if your battery voltage is below 12 volts.

 

[IJ.]

"Bob"

 

[Tae361]

First off, the white wire is connected to the black B2 wire via a fusible link (the symbol that you didn't know what it meant). The symbol looks like a long streched out S.

Is your battery at full charge?
As I recall (and someone will surely correct me if I'm wrong), the ECM will not let the ignitor fire if your battery voltage is below 12 volts.

I'm not sure if my battery is fully charged, i charged it a two days ago when i initially was ready to start my car, tried to start it probably 30 times trying to find out what is wrong, i'll keep it connected to my truck when I try to turn it over again tomorrow.

About the fusible link I know all about that now, since I fried it before when I connected the white wire to the negative side assuming thats where it belonged(marked it negative). I replaced the fusible link today and was attempting to start the car without the white wire connected because I didnt want to risk damage to other wires... it obviously didnt work.

The white wire is obviously the back end from the alternator to the battery, and connecting it to the positive would make sense now that the current would flow in the right direction, where connecting the white wire to the negative terminal would oppose the flow and spark like crazy.

 

[suprabad]

The white wire is obviously the back end from the alternator to the battery, and connecting it to the positive would make sense now that the current would flow in the right direction, .

That's correct, its a positive connection from the back of the alternator. I don't blame you for not wanting to connect it, nothing wrong with being cautious if your not sure.

...connecting the white wire to the negative terminal would oppose the flow and spark like crazy.

Correct again. It's the perfect definition of a "dead short".

Sounds like you're getting it under control.

 

[Tae361]

Sounds like you're getting it under control.

Well I'm still trying to link this to the fact I am getting no spark whatsoever when i turn the ignition. I am assuming that fuel is making it through the injectors because I opened the fuel sending line and the fuel return line and they both had fuel in them after attempting to start the car.

In the schematic for the charging system for the TSRM a lead eventually goes back into what i'm guessing is the 7.5 amp ignition fuse... The fusible link 1.25B would be the one that I blew. But I do not see how the fusible link 2.0L(headlight relay) shows up before it.
http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=042


In the schematic for the ignition system the same fusible link 2.0L shows up again which shows me that its on the same path coming from the alternator. However when it reaches the B-0 at the second split it says 7MGTE which left me confused (I have a 7MGE). Where it branches off it leaves me where I want to be however, going to the Ignitor and Ignition Coil. I am left to believe that this is not just true for the 7MGTE and they just put that there for the TCCS computer and the CPS (is this true?)
http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=040

When I trace the B-0 on the schematic for the TCCS it leads to the injectors.
http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=54

I made a little picture of the routing of the wires to try to figure out those crazy schematics.

 

[Poodles]

"bob"

EDIT: I give up, tried the smiley 3 times now and it's not working, go ahead and laugh mods...

 

[IJ.]

Which smilie?

 

[Poodles]

yours :rofl:

 

[Tae361]

well my whole theory went out the window, connected the wire to the positive and tried to start it and ended up blowing the 15A EFI fuse.. now i am really lost and have no idea what to do.

i could really use some insight on the situation

 

[Tae361]

I am attaching some pictures that I just took this afternoon after being thoroughly pissed off at the fact that I cant get something that looks so simple. Whatever I try, I end up blowing the 15A EFI fuse.

Here is some new images of the problems I am encountering and the explanation of each image (some may be redundant):

#1 This is where I have the positive cable connected to the positive battery terminal, note on this alternator there is a capacitor indicated at the arrow, which did not appear on my old alternator. I wonder if something in the alternator may have been damage when they washed the motor when I picked it up.

#2 Old alternator still on my old motor, there is no capacitor and some weird tab.

#3 This wire came off of my old alternator, it was clipped as shown. On my harness these two wires are black not white.

#4 This is the stupid wire that has been pissing me off for the past 4 days now. It is hot, I have no place to put it without blowing a fuse.

#5 This is the setup from alternator to battery as I remember it, but when I look at pictures of other peoples hook ups, it looks nothing like this at all.

I really need to know what the heck I am doing wrong here, and why this extra wire is hot and not a ground?

 

[osama1234]

Clearly some pretty knowledgable people have chimed in here, so its not necessary for me to even try to talk sophisticated, so i just did it the layman's way and had a look at my car.

I have a similar wire that comes from a bundle of wires underneath the fusebox, and it connects to the positive terminal of the battery. If your wire and its location of where it comes from and all match, we may have found it. (my wire happens to be blue underneath the black plastic insulator)

picture 1 shows this connected to the battery
picture 2 shows where the wire comes from, the bundle underneath the fuse box
picture 3 shows where this bundle of wire goes, towards the outside of the car into a Y-division of more wires.

As a last note, i noticed in your first post you connected this wire to the negative and your fusable link burned out. It all makes sense, that it is the positive (as people have suggested earlier), and any fuses currently blowing are related to some other issue that has been caused due to your miswiring or connecting this wire to the negative. (ie not because of this wire)

I once connected the terminals backwards (not just the one wire like you have, but both terminals entirely), and my fusable link blew similar to yours, but i also shorted my alternator. So its probably worth checking your alternator and other electronics connected to this fusable link (as shown the the TSRM (TEWD), cuz something there could have been shorted and ruined.

Hope this is helpful.

 

[Poodles]

Dunno WTF that thing is on the alternator, personally I wouldn't trust it as it's obviously not stock...

 

[Tae361]

As a last note, i noticed in your first post you connected this wire to the negative and your fusable link burned out. It all makes sense, that it is the positive (as people have suggested earlier), and any fuses currently blowing are related to some other issue that has been caused due to your miswiring or connecting this wire to the negative. (ie not because of this wire)

I once connected the terminals backwards (not just the one wire like you have, but both terminals entirely), and my fusable link blew similar to yours, but i also shorted my alternator. So its probably worth checking your alternator and other electronics connected to this fusable link (as shown the the TSRM (TEWD), cuz something there could have been shorted and ruined.

Hope this is helpful.

Thanks, I will swap my alternator from my old motor to this one, since it may be the problem you suggested, I checked all parts of the iginiton for failure except the alternator and everything was good.

Dunno WTF that thing is on the alternator, personally I wouldn't trust it as it's obviously not stock...

This is the alternator from the JDM cressida motor that I bought, it is alittle odd looking but it is a toyota product.

 

[Tae361]

This is really getting on my nerves now, I have to travel to go work on my car to only get the same results.

So this time I hook up the "unknown wire" to the positive and turn the ignition to on and pop there goes the 15A EFI fuse again.

So I tested every single part of the EFI system for resistance, everything came up with a strong result except the ignitor. The TSRM has the ignitor at 0.2-0.3 Ohms and I measured it at 0.6 Ohms.

I also tested the "unknown wire" for voltage in certain situations. When I tested it on the positive terminal it gave me a -0.00 reading, on the negative terminal it gave me a ~12V reading, and when I tested it on the ground screw near the fuse box it gave me a ~12V reading.

I also checked the ECU for battery power and it read ~12V. Cant really check much else because you know cant turn the ignition without that fuse blowing.

I dont know whats going on with this car, could the added resistance mean that my ignitor is bad and that is whats blowing the fuse?

 

[YotaRob]

that lil thing on your alt is a capacitor. leave it there its stock on some GE models. and it looks like you have your ground wire used as a positive wire. I.E. where its attatched to your alt should be at the fender, where its at the starter should be on the block, and attatched to neg post on batt. that "NAME THIS WIRE" should be hooked to positive, you whould have one near the fuse box that has two leads out of box into one loop, that goes to your alt. and you should have one big single wire that runs from the positive post of your batt directly to the starter post.

 

[Tae361]

that lil thing on your alt is a capacitor. leave it there its stock on some GE models. and it looks like you have your ground wire used as a positive wire. I.E. where its attatched to your alt should be at the fender, where its at the starter should be on the block, and attatched to neg post on batt. that "NAME THIS WIRE" should be hooked to positive, you whould have one near the fuse box that has two leads out of box into one loop, that goes to your alt. and you should have one big single wire that runs from the positive post of your batt directly to the starter post.

what youre saying is the black and yellow wire is the ground and the whole thing which leads to the starter should be hooked up to the negative, and the black/yellow is hooked to the fender.

the wire "name this wire" is hooked to the positive

so i pretty much have the terminals hooked up backwards?