2023 Smart Alternator incompatible with DC-DC Charger

Who has a newer tacoma with 'Smart' alternator and has successfully accompolished DC-DC charging?

I ran 6awg pos and negative from tacoma battery (not from alternator) to inline 40A fuses, back to rear bumper Anderson Connectors.
In camper, I installed a Victron Energy Orion-Tr Smart 12/12-Volt 30 amp 360-Watt DC-DC isolated Charger, outputs direct to camper 12v batteries.
Spot voltage measures show that Truck input of 13.1 to 13.3v (after voltage drop) is buck boosted to 13.8 to 14.4v (selectable) charge.

BUT the sine wave cycle of the "Smart" Alternator drops each minute to near zero and fools the DC charger into shutting down for a minute or more (every minute).... so no charging occurs.
Reprogramming DC charger fails to overcome this issue.
(Tacoma 130amp "smart" alternator part#27060-0P460.)

Looking for a fix:
1. Do I need a plain jane alternator that is NOT SMART and does not cycle to low voltages? Or is the truck ECM the culprit as suggested in a 2022 posting?

2. Would a high-output alternator overcome this issue?
If the Tacoma needs 130a and I am charging camper at 30A plus voltage losses and device inefficiencies it seems a 185 to 200a alternator might be in order. Concerned the ECM will still cycle the output.

 

By "Smart" I believe you are referring to the LIN control of the Tacoma Alternator. The Engine ECU supplies that LIN control. Much like a CANBUS, but a lot slower.

In my monitoring of the alternator output, I've never seen my output drop below 12.8 (except when engine starting) and ranges up to 14.6VDC. How are you seeing a sinewave on the DC power leads? If I ever saw a sinewave on the alternator, I would think an alternator diode was bad.

Have you monitored the alternator without your extra circuity connected?

Please link this 2022 posting!

I have in my info a 180Amp Toyota alternator as part number 27060-0P420 and DC Power Engineering put out a higher amp alternator too.

I don't know what the current draw of your system is going to be, but I would have put in a bit larger cable to the rear of the truck. In fact, I have, I've installed 4/0 cable from the engine compartment to the spare tire. This is not yet in use for its desired intentions which is a rear winch. Frame will be the ground return...

 

A voltmeter on truck or on input lines to converter seems steady. The dc converter itself (Victron app) and the output are fluctuating. Don't know what to make of it.

Here is someone who monitored alternator output loads:
https://www.tacomaworld.com/threads...alternator-loads-tested.821385/#post-29455226

 

@Dm93

@caribe makaira

 

I haven't read up on how the 3rd gen chargring system operates but looking at the wiring diagram it doesn't appear to really a fully smart charging system but the alternator is PCM controlled so output voltage and current will likely vary unlike older systems that used a fixed voltage based on temperature.

Many smart systems will lower alternator output when there is low electrical demand and the estimated battery state of charge is good, Ford and GM smart charge systems for example can range from 11.8v to over 15v when running.
I can't tell you how many customers I've had with GMs come in with a charging complaint because they see their voltmeter drop below 12v and there's absolutely nothing wrong with it, it's just how the system works. There's data pids on those that show desired and actual output and what "charging mode" they are currently in.

 

With my 2023 Tacoma I wanted a portable power setup, so I went with the National Luna DC25 Power Pack. It was more than the cost of created or piecing together my own set up, but I'm 100% satisfied.

For the 2023 alternator they have an ignition source sensor that plugs into an ignition hot source then into the Power Pack. You can use the cigarette lighter connector or hard wire it into an ignition hot source. This compensates for the variable output of the "smart" alternator. It has worked flawlessly.
This power pack is great if you plan on using it in different vehicles or when/if you power goes out in your home.

https://www.nationalluna.com/product/power-pack-dc25/
https://www.equipt1.com/products/ignition-sensor-cable

Cheers

 

i've read in the past that many honda's dating back to 2005-ish also had a similar alternator cutout system in place for their 'eco' mode to reduce driveline parasitic losses, and had similar issues with complaints.

i think the ignition trigger method mentioned above my post is going to be the most realistic way of going about this.

 

Did the same thing on my 2020 for a Redarc controller. Small wire through the firewall to an add a fuse tapped into an ignition on fuse and then to the charge controller. Tells the charger if the engine (alternator) is on or just the solar panel.

 

I'd just call the company to see if they have any experience with this.

 

This is exactly why you have to add extra circuitry to "fool" the system if you put in a Lithium Iron Phosphate battery.
Love the Tacoma but yeah, Toyota clung a little too long to 2004 technology.

 

I like the older non smart charging systems, checking them for a charging concern is as simple as voltage checks on a couple wires. The smart systems you need a scan tool, a scope, and know theory & operation to do a proper checks on. And we all know they typically don't put alternators in a user-friendly spot to get to.

 

Truck battery at rest 12.6V. Running at idle or 2500 rpm both 13.9V. Getting 13.9V at rear bumper Anderson terminals and at input to Victron converter. Autoranging meter fluctuates hundredths but these are pretty close.

Amperage at truck negative ground lead with no accessories 12.6Amps; all accessories runing 33.75A. So the Tacoma 130A alternator has lots of capacity available.

Victron input is 13.8V to 13.9V, no detectable voltage loss over the 6awg wiring from truck.
Victron output is *programmed* at 14.4v and reads this when I cut out the Tab battery terminal breakers. When I snap on the Tab battery terminal brakers the output reads the same as the tab battery, roughly 13.3V at moment. I used the Inverter to draw down the battery from 100% to 85% for the purpose of testing DC charging.

20A Victron DC charger behavior continues to cycle between starting to charge and promptly plummeting to zero charging for a minute, then repeating.

if I set the Victron to Engine Shutdown detection ON (the default to keep from draining your auto battery) the Victron high draw is a brief instant of perhaps 22 amps that dwindles down to zero with a few seconds.

If I set the Victron to Engine Shutdown OFF the Victron high draw is a brief instant of 35 to 37 amps that dwindles down wotihin a few seconds. After two or three cycles this pops the 40A engine compartment resettable breaker.

If someone with a 3rd gen. 2016 through 2024 Tacoma that should have the same alternator, and has a Victron DC charger, can pass along their Victron settings I'd be grateful. Here is what I have at the moment:

 

Following because I was thinking of getting a similar Victron. What happens when you set the Alternator Settings | Shutdown Voltage to say 9V. Does the Victron keep running? Perhaps you have higher frequency voltage fluctuations that are not detected by DVM. Just an idea.

 

Good idea! Or perhaps this manufacturer considers this on/off to be their PWM charging.

 

Good thinking. I'd tried loads of settings down to 5v. Kept popping 40a inline fuse to tow vehicle. Since ratings are 30a draw 20a charge that's discomforting. I have 60a fuses and another brand of dc converter on order to see if converter and not alternator is issue.
Quite certain there are 3rd Gen tacomas out there paired to dc converter. Like to replicate their settings.

 

@Max8

I don't see the alternator being a problem.

In the engine compartment there are two items that supply power, the battery and the alternator. They are tied together and collectively are suppling enough current to blow your user installed fuses, so source current is not a problem. The fuses are blowing because whatever is at the end of the truck is demanding more current than the fuses can pass.

Try running your setup without the engine on, just use the battery power, if the fuses blow then you will know it should not be the alternator. You may have already done this; I'm just trying to go back to basics without assumptions.

 

Does anyone have the same setup?

Working but poorly. Upped inline breakers to 60a as the device app monitor and clamp ammeter agree the charger is pulling a fluctuating max of 39a input and 19a output. Rapid decrease to zero then starting cycle over and over as the device turns OFF and ON.
Swapped another brand and a duplicate model to no improvement.
Manufacturer rep no help at all, no technical knowledge could only offer to test and swap unit by mail.
On a trip and getting charging about 25% effective time.
The Victron app and my victron digital battery monitor both report fluctuating input current dipping below 10v in a sine wave fashion.
I do not detect this with either of two digital voltmeters.
This low sine causes the converter to perceive Battery Off and kill charging.
I can change settings real time through the app and shrink the Off-On cycle to 20 seconds or so but still means effective charging is a fraction of time.
Setting the Off voltage detection below 12.7v ( now at 5v to shorten off cycle!) means this will suck my truck battery dry if engine not running. So on trip I pop hood and flip inline breaker every time we stop. Device seems to be causing slow drain of truck battery regardless. 1200 miles and truck is 12.4v not 12.7v resting. Scangauge reading of 13.8 running is now 13.3 to 13.4 with dc charger breakers off.

Who has a newer tacoma with 'Smart' alternator and has successfully accomplished DC-DC charging? Brand and model?

 

So I didn't use this setup for very long so I cannot comment on long term usage cases, however I did have a Renogy 50a DC-DC charger hooked up to a 100ah renogy LiFePo4 battery I had in my truck bed. I didn't end up using it as much as I thought, so I took it out and just got a larger starter battery to run accessories off of. I can confirm it would use the alternator to charge and I didn't have any issues like you're describing where it would cut out and cycle. So I'm wondering if this is a DC charger issue on your unit.

This is the DC to DC charger I had here and battery here. I don't have any great pictures of the setup because I was dealing with a fractured ankle at the time, but I can tell you I didn't have any issues with this setup and it would regularly charge that battery at 40a (you can change all these settings in their app). I have little experience with Victron personally, but I do know they can be very sensitive and usually need programming, this Renogy was good to go out of the box with no issues, hope this helps.

 

@K9tacoma Thank you, helpful to know something worked. I briefly tested a new Renogy 20a DC DC charger without success. It needed a separate third a wire providing ignition status. I ran a 12v lead from camper batteries to tell it the engine was on. Unable to get the device to ever go on ( no lights).. My replacement Victron charger arrived and I gave up on the Renogy on the premise the variable charging inputs were confusing it. If you have a 2023 then mine should have worked as well!​

After this trip I will ask Toyota to verify the truck charging system works correctly.

 

Not a problem! I did have to run a third ignition wire and ran it to the wiper fuse I believe, I can't recall exactly but I made sure it was a key on power source and that would kick on the charger no problem!