Alternators not charging (1 Viewer)

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Borger texas
I replaced my alternator and it isn’t charging, the old one wasn’t charging as well, what should I check? I have looked at my fuse all are good, any help will be nice
1973 fj40
 

ToyotaMatt

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stand by for some pics

i have your prescribed remody up in a moment
 

ToyotaMatt

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ok ,

look closly at the fire wall under the brake master , see that little black box ?

i am going to assume since you have a 73 , your bl;ack box has a 3 wire little black connector plug too on its pigtail ?

that's this live part here below

its called a Voltage Regulator

any time you replace your alternator due to unit faluure , its TEXT book VIAS Toyota's College level T-TEN program to go ahead and

replace the much lower pocket change at the tome regulator too in tandem
 

ToyotaMatt

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ok ,

look closly at the fire wall under the brake master , see that little black box ?

i am going to assume since you have a 73 , your bl;ack box has a 3 wire little black connector plug too on its pigtail ?

that's this live part here below

its called a Voltage Regulator

any time you replace your alternator due to unit faluure , its TEXT book VIAS Toyota's College level T-TEN program to go ahead and

replace the much lower pocket change at the tome regulator too in tandem

please click this LINK for more info and TECH too :




1606709623283.png



p[l
 
Joined
Oct 17, 2020
Messages
16
Location
Borger texas
ok ,

look closly at the fire wall under the brake master , see that little black box ?

i am going to assume since you have a 73 , your bl;ack box has a 3 wire little black connector plug too on its pigtail ?

that's this live part here below

its called a Voltage Regulator

any time you replace your alternator due to unit faluure , its TEXT book VIAS Toyota's College level T-TEN program to go ahead and

replace the much lower pocket change at the tome regulator too in tandem

please click this LINK for more info and TECH too :




View attachment 2510944


p[l
I replaced that and still not charging, where should I look beyond that?
 
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Bakersfield, Ca
what does the connection look like at the alternator? To confirm with a DMM you're just reading battery resting voltage when car is on?

All you did was replace the alternator, any pics? It runs fine besides that?
 

Steamer

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This may help to diagnose & show how it works.
Can you post some pics your voltage regulator showing the connections? The alternator also.

AltRegLgnd 02.jpg
 

73FJ40

After another night of rust removal!
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Your white/blue alternator output wire is a short circuit waiting to happen. Has all that stripped insulation exposing copper wires indicative of the cable pulling out of the crimp connect?

Also, the wires in your new connector at the alternator don't match the colors of the wires entering the connector at the regulator. Have you double checked to make certain they match the schematic provided by @Steamer ?
 
Joined
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Borger texas
Your white/blue alternator output wire is a short circuit waiting to happen. Has all that stripped insulation exposing copper wires indicative of the cable pulling out of the crimp connect?

Also, the wires in your new connector at the alternator don't match the colors of the wires entering the connector at the regulator. Have you double checked to make certain they match the schematic provided by @Steamer ?
Oh there another plug you can see in the picture what connects to the VR, that just the plug that came with the alternator
 

Cromagnon

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Can you take a picture of the connectors at the voltage regulator showing both connectors mated and the wires fanned out to see what the wire color codes are? Can you also do the same thing for the connector from the alternator to the voltage regulator? Fix the WL wire and make certain that you disconnect the battery before working on it. (Edited to correct spelling)
 
Joined
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Messages
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Location
Borger texas
Can you take a picture of the connectors at the voltage regulator showing bot connectors mated and the wires fanned out to see what the wire color codes are? Can you also do the same thing for the connector from the alternator to the voltage regulator? Fix the WL wire and make certain that you disconnect the battery before working on it.
I will tomorrow when I get off shift,
 

Cromagnon

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Colorado Springs, CO
Those pictures are good, thanks. Make sure the wires line up on the voltage regulator connectors. It looks like they do but you will be able to tell better in "real life" than anyone with a picture. The two connector plug is for the alternator, correct? Make sure the WG and WB wires do, in fact, go to the voltage regulator. What has caused the WL wire to lose its insulation at the connector like that? Certainly could be part of the problem and if it isn't now it most probably will.
 

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