tmxmotorsports
SILVER Star
Swap another battery in and prove toyota wrong
FJ80 Battery mystery, won't start nor stay running.
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Have you checked all the cables to the starter?
tmxmotorsports
SILVER Star
It starts with a jump box this shouldn't be a cable problem.
I have seen it before
I normally hate to just throw parts at a problem that is not 100% understood. That said... Replace those tired, nasty battery cable ends with some marine style brass ones. I do that on ALL of my rigs as soon as I get them. I am wondering if the current is not easily making it from the battery post to the batery cables du to the cable ends. (yes, I have seen it happen). The jumper cables *may* be bypassing the trouble point. In any case it is an upgrade that I consider not really even an upgrade, but a correction to an OEM weak point.
Amazon product ASIN B0882PCBDC
Edit: Also, have you cleaned/wirebrushed the battery terminals and the terminal connection on the cables?. Even if they look "clean? Sometimes there is oxidation between them that at the worst is merely dark looking, but does a surprisingly good job of degrading the contact. Get those surfaces bright and shiny.
Mark...
Amazon product ASIN B0882PCBDC
Edit: Also, have you cleaned/wirebrushed the battery terminals and the terminal connection on the cables?. Even if they look "clean? Sometimes there is oxidation between them that at the worst is merely dark looking, but does a surprisingly good job of degrading the contact. Get those surfaces bright and shiny.
Mark...
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- Thread starter
- #26
Yes, that was one of the very first things. Wire brushed both.
I have no problem incurring those, thanks. Ordered!
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Have you tried measuring for a voltage drop from the battery post to the cable terminal?
Like this.
Don't attempt to start it, just turn on the headlights, with high beams, and measure with the two probes as shown in the picture. Now, my meter is set to millivolts, so that's 1.3mV of drop from the post to the terminal even with a good connection. It's tiny, but it IS measureable.
Your meter may not measure millivolts but that's ok, if there's a bad connection it will probably present as whole-Volts.
Do this for both positive and negative terminals.
Good luck.
There is no way that battery terminal could be considered clean. Create a watery paste of baking soda and water in a small container and soak the cable end and battery clamp for several minutes and afterwards dump it over the battery terminal to neutralize the acid and corrosion.
As opposed to just ignoring the suggestions that folks are giving you, perhaps it's time to do a little troubleshooting. For that to be successful, you need to start at the beginning. Or you could just continue to ignore suggestions and keep guessing.
those terminals are shot
get a second hand and meter the voltage across your starter while attempting to turn it over. if your voltage is similar to the metering at the battery, you have a bad starter.
it is very simple to get cables made locally without the need to use some subpar replacement junk
get a second hand and meter the voltage across your starter while attempting to turn it over. if your voltage is similar to the metering at the battery, you have a bad starter.
it is very simple to get cables made locally without the need to use some subpar replacement junk
- Thread starter
- #32
Jon, I have no idea why you think I'm armcharing this. Is there a suggestion you feel I've ignored?
- Thread starter
- #34
Did that exactly and I have zero discernible needle movement (2.5VDC scale) with either polarity on either terminal
- Thread starter
- #35
Those terminals are old leaded marine terminals. Just one extra wire there and I've run it to the body panel for extra ground a long time ago.
tmxmotorsports
SILVER Star
I use those same terminals on my builds. Nothing wrong with them. Once again swap the battery out.
I asked you to check all 3 fusible links. You checked 2 of them.
@tmxmotorsports suggested that the battery voltage when running is low. It should be around 14.4 VDC right after startup. Your voltage indicates either a failed battery cell or a failing alternator, or a resistive cable. He asked you 3 times to change the battery.
I have been troubleshooting electronics for the last 40 years. You don't assume anything before verification. As soon as you start to assume a component "can't be faulty because XXX" is when you go down the primrose path. You must first verify and then move on.
It has also been well documented that fusible links can become intermittent due to age and vibration. They each have a flameproof silicone jacket so you can't tell by simply looking at them. Some folks have been able to simply pull them apart while they looked good from the outside.
For the $12-$15 that they cost, they should be replaced with every battery change IMO.
For the $12-$15 that they cost, they should be replaced with every battery change IMO.
tmxmotorsports
SILVER Star