Voltage Discrepancies (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Jul 1, 2019
Threads
31
Messages
214
Location
San Antonio
Mudders,
Truck is an 11/1974 F1.5 retrofitted with a 2F alternator bracket with internally regulated FJ60 alternator and coolerman's wiring. External regulator is deleted.
I have recently installed a sniper and noticed the voltage seemed a bit low driving around. Around 12.2 to 12.5.
When I get home I checked the alternator and get 14.38V
The battery shows 13.56V
But the sniper readout is showing 13.1V. I drove the cruiser multiple times throughout the day and it never read above 12.5V so not sure why it does now.
Question is: Is there that much voltage drop in the harness or do I have a problem somewhere?
Thanks in advance!

IMG_7174.JPG


IMG_7175.JPG


IMG_7176.JPG
 
Any wiring diagram for the sniper? Is the alternator wired directly to the battery, or does it charge on the harness side of the fusible link via the ammeter?
 
that is NOT a Genuine NipponDenso OEM Alternator of any kind ...

its a imposter from ROCK AUTO


am i correct ?
 
@ToyotaMatt It is an autozone alternator.

Sniper main power is wired directly to the positive post on the battery. Ignition is signal is wired to the emissions control power, which is not being used otherwise. Everything else is internal to their harness.

Alternator wiring is through the ammeter and original, just no external voltage regulator. I spliced coolermans's wire to my existing alternator main wire and ran it back through back from the drivers side to the now passenger side alternator. I do not to my knowlegde have a fusible link, at least I didn't inherit one with the cruiser.
 
A fusible link can be had locally at autozone. Install it right away. It is going to be slightly smaller (in diameter) than the original battery + wire in the main harness. I don't know if that is two gauges, or what, the point is that you have a consumable in the harness that could prevent a bigger melt-down.

Uncertain about the voltage still...
 
@ToyotaMatt It is an autozone alternator.

Sniper main power is wired directly to the positive post on the battery. Ignition is signal is wired to the emissions control power, which is not being used otherwise. Everything else is internal to their harness.

Alternator wiring is through the ammeter and original, just no external voltage regulator. I spliced coolermans's wire to my existing alternator main wire and ran it back through back from the drivers side to the now passenger side alternator. I do not to my knowlegde have a fusible link, at least I didn't inherit one with the cruiser.

not sure about a locally sourced 60 series fusible links ?

but have you found yours to be faulty ?
 
Never had a problem with RockAuto.


my point is , its NOT and never was a correct alternator as in DENSO , or NipponDenso unit


i see one RED FLAG here : ⛳


- you have a 4cylinder Toyota CAR battery , that's like a group 35 series or smaller NOT the GROUP 27 series that's supposed to be in there ......🤔

- go to your local toyota and start out with the correct battery , this may in return smoke out your issue at hand when you will be neatening up all the various wires attached to that under sized battery


- have the battery manually load / bench tested while your replacing it too , this may help diagnose your electrical gremlin too ?
 
Mudders,
Truck is an 11/1974 F1.5 retrofitted with a 2F alternator bracket with internally regulated FJ60 alternator and coolerman's wiring. External regulator is deleted.
I have recently installed a sniper and noticed the voltage seemed a bit low driving around. Around 12.2 to 12.5.
When I get home I checked the alternator and get 14.38V
The battery shows 13.56V
But the sniper readout is showing 13.1V. I drove the cruiser multiple times throughout the day and it never read above 12.5V so not sure why it does now.
Question is: Is there that much voltage drop in the harness or do I have a problem somewhere?
Thanks in advance!

View attachment 3198494

View attachment 3198495

View attachment 3198496


- lastly sandwich stacking all those terminals creates resistance between them, each one adding to the over all lack of current flow ,

polish them all BRIGHT before re-assy .



- set your self up for success using the correct battery group 27 series TRU-START , they are TOUGH as Nails and COLD CLIMATE / Arctic Spec. rated also .................fyi


- the upped CCA factor will simply amaze you as well too
 
Sniper is wired directly to the battery it should read the same unless i'm missing something. Is there a way to calibrate that read out on the sniper maybe it's off?
 
There has to be something inline causing that voltage drop after the alternator. The alternator seems to be working just fine since the volts are good at the post. What is the battery voltage when the truck isn't running? Can you measure volts at the next junction after the alternator? Maybe you can work your way down the line to see where the issue is.
 
@cstav86

I wonder if the local Toyota dealer in San Antonio carries "Arctic rated" batteries. Kind of contrary to the climate change political narrative!

Your stack up of positive and negatives connectors on your battery is incredible. @ToyotaMatt is correct to point out those stacks of terminations need to be cleaned up.

I suggest, as a diagnostic test, you run the feed to the Sniper system directly to the alternator. That will determine whether the Sniper is reading wrong or there is voltage drop through the stack of terminations.
 
I bought this battery during the pandemic when batteries were scarce. Every time I have been at the dealer I hear them saying they are out of batteries to some customer.
Overall thanks for the troubleshooting recommendations. Any suggestions to clean up the "stack"??? Do I need a separate fuse bank for these?
What's on there are:
Winch
H4 toyota headlight harness
Sniper
Air compressor
One more, but can't recall sitting at my work desk.
 
@cstav86

I wonder if the local Toyota dealer in San Antonio carries "Arctic rated" batteries. Kind of contrary to the climate change political narrative!

Your stack up of positive and negatives connectors on your battery is incredible. @ToyotaMatt is correct to point out those stacks of terminations need to be cleaned up.

I suggest, as a diagnostic test, you run the feed to the Sniper system directly to the alternator. That will determine whether the Sniper is reading wrong or there is voltage drop through the stack of terminations.
I bought this battery during the pandemic when batteries were scarce. Every time I have been at the dealer I hear them saying they are out of batteries to some customer.
Overall thanks for the troubleshooting recommendations. Any suggestions to clean up the "stack"??? Do I need a separate fuse bank for these?
What's on there are:
Winch
H4 toyota headlight harness
Sniper
Air compressor
One more, but can't recall sitting at my work desk.


battery for FJ40 TRU-START part # 00544-27060-675

- you need a group 27

NOT A 27F


TRU-START OEM batteries are made for TOYOTA by interstate , but to a much higher quality in general :D
 
you have been .🍀 ........
I haven't really had to use RockAuto for the FJ40. There are tons of Land Cruiser options out there that already sell better stuff. I believe that you can purchase Aisin stuff thru them? Maybe it is a Aisin clutch part something? Their search is really easy/fast, which isn't bad if it is a last resort. Some of us still rock holes in our socks.
 
not sure about a locally sourced 60 series fusible links ?

but have you found yours to be faulty ?
Yes, source a correct fusible link. Why a 60-series in the 40 forum?

However, I'm not unsure that the generic stuff, even an inline blade fuse, isn't a bad thing until stuff arrives. He didn't find a fusible link, and neither do I from the photo.
 
I would not worry about the voltage discrepancies. I doubt the Sniper's built-in volt reading component is of high quality or all that accurate. Why would it need to be? The only use I can see it providing is that if the Sniper is getting less than 12V. And if that happens, you then need to pull out a quality meter and start diagnosing your electrical system. If you’re looking to monitor system voltage on your dash, then I would suggest installing a quality dash mounted voltmeter.
 

Users who are viewing this thread

Back
Top Bottom