What the hell is going on???
- Thread starter Liam
- Start date
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If you have a HIGHER than stock output Alternator the stock AMP gauge will not read the same as with a stock output one. Anyone that has an FJ40 w/ a stock harness should know their wiring diagram by heart, it will save your ass more than you can imagine.
I had a simular issue with my 60. Turns out that I had a dead short in the battery. The battery tested great until you applied a vibration or shock. I took the battery to a reliable battery shop and they discovered the problem with a couple quick drop tests... 2-3 inches off the ground with the test equipment attached. The battery was a Interstate "Redtop". I installed an Optima Redtop and never had a problem again.
- Thread starter
- #44
well, first off i dont have a meter to test it......i dont suppose i could stick my tongue on it and get an idea....What is the voltage across the battery terminals with the engine running.....I meant the CURRENT BATTERY, not the old one that you had tested 6 years ago.....
My ammeter runs dead center until I turn something electrical on then it bounces, but seems to charge and run just fine so I just don't worry about it. I have a solid-state VR, too.
Ed
secondly, now that i have changed out the Alt, VR, and battery and have also changed around the wiring correctly my LC has come back to life.....
i'll take it over to Auto zone tomorrow or maybe i'll go get a meter...
bsevans
Focus on the Journey
This is a SS VR and the blue wire is for supression to reduce the static on the radio.
- Thread starter
- #47
that is now what my VR looks like. Autozone has them in stock, which surprised the hell out of me..
So.....what was the outcome of this clusterfxxx?
short?
A higher than original amp rating for the alternator should not make the ammeter read higher under normal loads it should still achieve a steady state of near zero which shows the battery is charged.
The higher rating just means you have more capacity----btw sometimes more capacity than the ammeter can stand!
https://forum.ih8mud.com/40-55-series-tech/282419-amps-too-high.html
So if the AMMETER is constantly showing that it is charging then something is drawing all the time and the battery is never fully charged, could be a short as mentioned and the old alternator just could not keep up with it but the new one is. Make sure you are right about the wiring too, Can you post a pic of the alt and the connections?
One way to check for this would be to check for parasitic battery drain if the battery goes dead while it sits--just disco the pos lead of your batter and use your multimeter to see if you are drawing with it just sitting
The prob with shorts is isolating the offending ciruit ---symptoms can sometimes tell you but sometimes (like with the radio) you may just be adding an additional drain it cant handle
With it running you can look for shorts by pulling fuses except for the ignition of course but you could hotwire it with a wire from your battery to the coil then pull the ignition fuse the run it for a while and and see if the battery still drains or if the ammeter returns to normal
Since you seemed to have the prob with the radio I might just disconnect the wire for the radio and see what happens
A higher than original amp rating for the alternator should not make the ammeter read higher under normal loads it should still achieve a steady state of near zero which shows the battery is charged.
The higher rating just means you have more capacity----btw sometimes more capacity than the ammeter can stand!
https://forum.ih8mud.com/40-55-series-tech/282419-amps-too-high.html
So if the AMMETER is constantly showing that it is charging then something is drawing all the time and the battery is never fully charged, could be a short as mentioned and the old alternator just could not keep up with it but the new one is. Make sure you are right about the wiring too, Can you post a pic of the alt and the connections?
One way to check for this would be to check for parasitic battery drain if the battery goes dead while it sits--just disco the pos lead of your batter and use your multimeter to see if you are drawing with it just sitting
The prob with shorts is isolating the offending ciruit ---symptoms can sometimes tell you but sometimes (like with the radio) you may just be adding an additional drain it cant handle
With it running you can look for shorts by pulling fuses except for the ignition of course but you could hotwire it with a wire from your battery to the coil then pull the ignition fuse the run it for a while and and see if the battery still drains or if the ammeter returns to normal
Since you seemed to have the prob with the radio I might just disconnect the wire for the radio and see what happens
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color code
i took a bunch of electrical tape off and traced wires back. Come to find out two of the wires were mixed up going into the Alt. Now my AMP meter is pegged to the right until i turn everything on and then it falls around 3/4 to 2/3 mark......
How many and what is the color of the wires and what does the connection on the ALT say if you cant take a pic?
should be letters or numbers near the terminals--is is an FJ40 alt or GM?
i took a bunch of electrical tape off and traced wires back. Come to find out two of the wires were mixed up going into the Alt. Now my AMP meter is pegged to the right until i turn everything on and then it falls around 3/4 to 2/3 mark......
How many and what is the color of the wires and what does the connection on the ALT say if you cant take a pic?
should be letters or numbers near the terminals--is is an FJ40 alt or GM?
Test and Eliminate
"So i stop to take a piss and when i get back in to start it the battery is completely dead. "
So did you try stopping and not taking a piss, or pissing and not stopping?---Just saying
It pays to use a logical process of elimination
"So i stop to take a piss and when i get back in to start it the battery is completely dead. "
So did you try stopping and not taking a piss, or pissing and not stopping?---Just saying
It pays to use a logical process of elimination
