replaced 1jz alternator and battery is still not charging

[87supraguy]

so this is the background on the car. i had the car running fine for a good while and one day after work i go to start it and the car is dead. i had my mom bring my truck and jump me. i figured something must have drained the battery or i left something on, i turn it on and drive it home. after driving 2 miles the car begins to sputter and dies (basically the battery couldn't keep giving sufficient power to coils there for weak spark and died) i had to get jumped again and this time drove it maybe half a mile and it died in front of my house but atleast i'm home. i jumped the car again and put a multimeter to the battery and could see that the battery was not being charged. i figured ok bad alternator. i took my battery to get charged at autozone and also had the alternator tested. the test surprisingly came back as a good but i was thinking a bench test would give a different result than one on the car with a constant load. either way i got another alternator that came off a known running 1j and put it on. put in my charged battery and monitored the multimeter and same issue the alternator is not charging the battery. belt tension is good.

WTF!!!!

i have checked all fuses to insure nothing is burnt out or anything.

my next guess is the 3 pin connector maybe something fubar there.
S- Sense
L - Lamp
IG - Ignition

anyone know if i am test the connector for flaws or issues, how should these be tested? in other words, at each terminal what kind of readings am i looking for?

i just need to figure this out. IF you have any other Ideas on what it might be or other methods to get it figured out, it would be greatly appreciated.

 

[S.A. supra]

Is the battery holding a charge? I had the same problem, once. I took the battery to get check and the said it was still good. So I go back home and check the alt it checked out good. I put the battery back in, it ran for awhile then the same issue. I take the battery back again they charged it again. And told me to check all my connection. So I do, and same thing happen again. So I took it to a different advance auto and right away they tell me its a bad battery. It was still under the warranty, so they gave me a new one. I had no problems after that. Check your connections first and take your battery back and get it checked.

 

[87supraguy]

yeah i had warranty on the battery and replaced it. right now the battery is holding a 12.56 charge and slowly begins to drop once the car is on. so to clarify, i have a new battery had it for 6 days now, i put new battery terminals (Gold Plated) so connections to battery are goodthick guage wire fire alternator to fuse box is good.

 

[destrux]

Get a multimeter and test the voltage at the alternator, right on the main +B stud (with the car running). If there's voltage there check the alternator main wire leading to the battery and the fuse and fusible link. There may be more than one fuse on that wire, my car has one in the fuse box (a huge one) and a fusible link wire between the fuse box and the (+) battery terminal.

The tests for the regulator and it's wiring have been posted before, and is on the net otherwise, so I won't rehash it here, just google "toyota alternator regulator test".

 

[slowmedown]

damn your mom had to bail you out?

you checked all your grounds?

 

[87supraguy]

awesome i will run this test tomorrow morning,

haha yeah my mom had to come get me least she could do since she was using my truck. yeah all grounds on firewall and by fuse box are accounted for... but will double check everything again

 

[SupraMedical68]

I hate say to the obvious things, but I had a similar problem once as well. I replaced the alternator with a new battery few years ago, but I also needed new connectors for my postive and negative battery terminials.

 

[87supraguy]

also things i have also done replaced battery terminal, found a thick guaged wire (that is suppose to be grounded to the block but was not) and bolted it to the block, put in a 100 amp fuse and still not charging

here's a quick pic of my current set up.

 

[87supraguy]

anyone else have any ideas? again does anyone know how to test the 3 pin connector at the alternator, like what to look for in the readings?

 

[bioskyline]

the tsrm will help you, the 3 pin plug is for the rectifier bridge and diodes, so test will be the same as a 7m alt, or any 3 pin plug japanesse alt really

could be a broken wire or bad connection there

 

[87supraguy]

soo another update. just drove to autozone and had them retest with the alternator on the car again and the test was still a negative on the charging but was told it was a failed voltage regulator. this is a start but the alternator is off a good running motor... another bad alternator?

 

[mk3_7m]

Check the alternator wires for splits.

 

[87supraguy]

got the alternator rebuilt and the guy said it looked in great shape and no issues with the voltage regulator if anything the brushes could be changed but didn't look bad. ran me $25. i get home with the alternator put it on and still not charging. then look to the connector again... the wires at the connector look good so i start cutting away at the loom to follow the wires and about 1.5ft from the connector there was a break in one of the wires where it was prviously soldered together. re soldered it and all of a sudden the alt is now charging!!!!

i'm soo happy its fixed but upset it took me soo long. either way thanks to everyone for the thoughts and suggestions!

 

[slowmedown]

awesome glad you figured it out

 

[87supraguy]

me too and i dropped off the supra at PSI to finaaly get tuned. wish me luck.

 

[GrimJack]

Another possibly culprit - I realize you're solved now, but for the sake of future searches - if you've repainted your engine bay, remember to scrub the paint back down to clean steel where the alternator ground cable connects.

 

[slowmedown]

good luck with the tune