LJ78 Prado warning lights on beeping? (1 Viewer)

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My 91’ Prado warning lights on the dash all illuminated and it kept a steady beep (the same one that sounds before the vehicle can start). Turns out a terminal was loose, fixed that but now the battery gauge is low and not rising while driving. All terminals/connections are tight, brand new alternator was installed. Anybody know what could be going on?
 
My 91’ Prado warning lights on the dash all illuminated and it kept a steady beep (the same one that sounds before the vehicle can start). Turns out a terminal was loose, fixed that but now the battery gauge is low and not rising while driving. All terminals/connections are tight, brand new alternator was installed. Anybody know what could be going on?
I forgot to add the lights and beep came on while I was driving
 
I forgot to add the lights and beep came on while I was driving
Hi @manaraja

Sounds like the alternator may still be the issue. Make sure the connectors are clean, including your ground points.

Also check the error codes - https://www.google.com/url?sa=t&sou...cQFnoECA0QAQ&usg=AOvVaw2ZEef9dPf15WhOnH7XD43L

You should also check the wiring diagram on the forum.

There are also 2 X fused links on the battery terminals. Make sure they are okay. Also check and test your fuses.

Hope this helps.
 
@manaraja I have the exact same problem, right now, on my '91 LJ78 - single battery setup. I've confirmed with multimeter that the battery is not getting enough voltage while vehicle is running, which leads me to believe alternator is out. Voltage at battery drops to 11.8 when vehicle is on (with only radio and 3in1 gauge on), believe it should be around 14.2-14.7 if alternator is doing its job. 12.6v read on battery when vehicle is off is normal, so definitely needs to be above that to be getting charge from alternator. I've confirmed the battery (Diehard Red, only 1 yr old) is good. I'm hoping to have alternator refurbished and reinstalled. Right now I have the constant beep you describe, even when vehicle is off and key is out of ignition. Hoping alternator fix solves it, but hearing your experience makes me a bit nervous. I'll have to dig into wiring, fused links, and grounds a bit closer, too.

Did you get your issue resolved? Curious since we have exact same symptoms.
 
@manaraja I have the exact same problem, right now, on my '91 LJ78 - single battery setup. I've confirmed with multimeter that the battery is not getting enough voltage while vehicle is running, which leads me to believe alternator is out. Voltage at battery drops to 11.8 when vehicle is on (with only radio and 3in1 gauge on), believe it should be around 14.2-14.7 if alternator is doing its job. 12.6v read on battery when vehicle is off is normal, so definitely needs to be above that to be getting charge from alternator. I've confirmed the battery (Diehard Red, only 1 yr old) is good. I'm hoping to have alternator refurbished and reinstalled. Right now I have the constant beep you describe, even when vehicle is off and key is out of ignition. Hoping alternator fix solves it, but hearing your experience makes me a bit nervous. I'll have to dig into wiring, fused links, and grounds a bit closer, too.

Did you get your issue resolved? Curious since we have exact same symptoms.
Yes the issue has been fixed. One of the connectors to the alternator was loose. Plugged it back in and the truck is running no problem now. Hope you get to the bottom of your vehicle issues brother.
 

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