Wires To Alternator Help
 

Whats the three wires that join into a plug into the back of the alternator on a 1990 Turbo?:help:
It heads from the back of the alternator to the bottom of the fuse box. The wires are cut due to years of being angeled, i need to replace it. Could be the issue why my batt doesn't charge. Im wondering where or how i can replace this.

http://img18.imageshack.us/img18/44/p00036x.th.jpg

http://img35.imageshack.us/img35/8879/suprakt.th.jpg

Thanks seems like i have to get down in wiring it my way though correct? Since i do not think they sell any cables just for that.:rolleyes2

I don't understand what you are asking there.

Call a Toyota dealer in your area, they may be able to order a pigtail you can just splice on, otherwise replacement plugs and terminals are available and you can do it yourself.

haha its alright ill do just that. Thanks for the wiring reference however:bigthumb: very helpful since my bay looks like a pit of snakes tangled with vines.

Thought I'd post my charging issues in here so as not to start another thread, I've got to check the wiring out with my multimeter yet but was wondering if anyone could offer help with these symptoms.

Basically the car's not getting any charge, and the battery light doesn't come on with the ignition OR when running, it does however come on during (and only during) cranking. When I pulled the alternator apart the brushes looked worn but they're still touching the sliprings with good pressure & I've cleaned them up too. Everything checks out internally, no broken coils etc.

I'm just wondering with the absence of charge light except for cranking if it's likely to be the wiring or if the reg/rec/diode pack tend to fail. Hopefully I'll know more once I've tested the pin outputs but just searching for an easy option haha...

odd, yea im not a wizz at all this but what solved my problem is the good old fashioned process of elimination!
replaced alternator, battery, starter, ect. now it has come down to the wiring.
ill post again once i have it solved out.:dance:

I have it wired directly from the alternator to the battery.

Really easy to do. I can take pics if you like but I'm heading to work now and won't be home until really late.

Meter shows over 14.0V consistently so now my alternator charges my battery just fine. :dance:

Alright sounds good, id appreciate it if you did post these pics up, ill keep checking thanks!

Hold tight, I'll go take some now.

Here you go.

Really easy to do, like 3 min job.

Need 2 ends that can be crimped and some wires. I used 3 wires (don't remember what gauge) because I didn't have enough gauge wire for the power from alternator to battery. Better than have a little too much wiring than too little and causing heat issues I guess.

Ohhhhh okay i get ya, looks simple, except my issue here is not that cable, you see the one in the back of the alt. thats 3 wires, yellow white and another
thats what snapped on mine, but im going to try this method. Thanks very much:bouncy:

I have no idea what those wires are for.. are they for powering accessories? If they are, then what I did will not work.

I only did what I did because my alternator wouldn't charge my battery.

Ah i see, ill work things out and do the trial and error method. Thanks for the info tho.:x:

You should see around 13.5v to 14.4v while the engine is running; Measure it at the battery and at the alt and reference ground at both the battery and the at the chassis. A low reading at the battery but an acceptable reading at the alternator indicates a bad battery wire or fusible link.

Mark, at least add a fusible link to that wire... VERY bad idea just running it straight... your problem may only be that you need to replace the 100A fusible link as it is, but if you want to keep the added wiring add a 100A fusible link to it.


And BTW, incase some of you haven't investigated it before, clicking on the "Next Page" link on TEWD pages (like the one I posted earlier) usually brings up a page with collector illustration with pin numbering that matches the diagram AND troubleshooting tips.

Yea with the wires there I'm seeing about 14.2V, without it I only see like 12V which to me indicated a wiring issue.

I know I should've checked for fuses.. but for some reason, I don't have any memory inspecting the 100A fuse. lol I should go do that.

The fusible link seems to be the most common cause of voltage drop across the alt to battery line... more so than the barttery wire. This is more common in earlier MKIIIs as they use a fusible link wire as opposed to the sealed fusible link used in later models... fusible link wires are more prone to degradation over time.

BTW, you can switch the wire type out for a sealed link.

I should add that if you use the battery's negative terminal for your ground and measure a proper voltage at the alternator's output lug but the voltage at the battery is very low you needn't bother with the other wiring on the alternator, just follow the wiring from the alternator's lug to the battery.

You can also to a voltage drop test (negative test lead to the alt's lug and positive test lead to the battery's positive terminal), the reading should be very low, more than half a volt and you need to track the drop using the same methodology until you find the cause; You can do this test across just the fusible link to see if the fusible link is the culprit, but you have to pull the section it's mounted in out of the fuse box housing so I usually test the drop across the whole thing first.

Basically then, if the alternator's throwing out any charge then it should be evident across a chassis earth & the lug when the engine's running? I'm getting 11.69 & dropping with higher revs both across earth/alt. lug & across battery terminals. Everything seems to check out continuity wise with my wiring but still no charge. I'm beginning to think reg/rec failure...
:sadwavey:

Oh, another thing I noticed was after a ten minute drive the other day the casing of the alt was quite hot (if I'd really pressed my hand on hard it would've hurt). To me that says the thing's working but the charge isn't getting past the reg/rec...

I would just pull the alternator out and take to a parts store to have it tested... Here they all do it for free and it's easy to do. That's VERY low and below the ECU's minimum from what I've been told.

I 2nd that, get it tested. Some stores can test the regulator/diodes while it's on the car, so you literally just drive there.

I sometimes get that issue and am curious to how can i identify and replace the fusible link, cause all the signs point to that.

ALT 100A FL in the engine bay fuse box.

Some aftermarket power wires also have a FL in the middle of them; just a 1" to 2" sections of a different diameter is what you can look for.

Um... you know it comes out from the bottom, right? And you can use a sealed one as specified for later years in place of the wire if your car had the wire.

Then look closer... I'm not making it up. The top half and bottom separate and each section of the inside of the upper comes out individually. The fusible links do not pull out from the top.



The contained module versus wire is just a matter of preference and are interchangeable... it's just as possible that yours was replaced once already with a wire FL.... it's also possible that some jackass replaced it with regular wire (BAD idea).

nor did you from the start.... jebus, there's a time you just have to suck it up and pay a mechanic. All the parts you're looking at there are bits of the former FL.... OPEN UP THE FUSE BOX.

And there's nothing triple about that part... get it open, look what you're dealing with and don't be a dipshit (example below).


Yes, because engine fires only happen to the OTHER GUY and they're sooo much fun anyway.:uh:

I haven't had one apart in a couple years (since I replaced one on a friend's MKIII) so the finer points escape me. But it does come apart and there are two screws which clamp the 100A ALT FL in place from below. Unbolt the fuse box, lift it up and take a look around. You may need to feed more wire from the wiring harness into the bottom of the box to create sufficient slack.

Nothing should require significant force.