Ken the electrical guy Q n A

The tips of my multimeter, while small and pointed, do not seem to be small enough to fit inside the connector to touch the pins. Is it safe to touch the exposed part of the pcb to the ground? I assume it would try to turn the lights on when the ecu pin contacts ground

 

get a paper clip, tack, anything small and attach it to ur probe

 

Do i have to get a bigger battery if i add too many auxiliary lights?

 

How many lights are we talking? What battery do you have now? How many reserve AHs?

do you want to be able to run them without the truck on? For how long?

if you can tell me how many lights you have and their total wattage we can get into it

 

It’s just the recomended 12 volt ever start battery, I was just thinking about adding a small light bar to my bumper.

 

If you just want to run a light bar that you use while driving then your fine.

 

Sweet thx

 

No problem enjoy your new light bar

 

Ive got one for ya. Not automotive related. More or less for clarification, but its stumping me for sure.

So Im creating a voltage divider circuit so I can produce a 0-10V Analog signal from a 24V DC power supply. Its so I can simulate an analog input signal to a PLC controller. Anywho, this is where my math led me to, and what parts I ordered. (ignore the -24, I meant 0. And the +10V is showing what I should be measuring at that point with the pot turned to 5k)

A 7K ohm resistor, and a 5K ohm potentiometer. So I can get a reading sans multi meter, I ordered a cheap analog voltage gauge off Amazon.

$7 YXQ 0-15V Analog Voltmeter Panel 85C1-V Gauge Meter 2.5 Accuracy for Auto Circuit Measurement Tester

https://www.amazon.com/YXQ-Voltmete...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

So I got everything soldered up, and connected the analog volt meter to the wiper side of the pot, just in place of IV-1 in my schematic. Fired it up and got a 0-8V range showing on my cheap volt meter and on my Fluke meter, instead of 0-10V like I wanted. After hours of pondering, I disconnected that cheap gauge I got off Amazon and measured with my Fluke 77 by itself.

9.8 Volts. Perfect.

But why? Could that stupid little analog voltage gauge really be pulling a 1.8V load just to make the needle come up? I checked it with a 9V battery and its spot on, which is why Im stumped.

Oh, and with that analog gauge connected, the circuit was pulling 2.24mA at 8V. I havent checked it without the gauge yet.

 

@Kens04Taco Ken, I have a simple question for you. I have a switch with the 4 common wires (green,black,red1 and red2) that I installed to the left of the steering wheel in my 2019 TRD Sport. I plan to use it for a tailgate opener in the future. In the meantime I just want the switch to light with my dash lights. I think I only need to wire the red2 and black. Is this true and if it is where can I tap into. Maybe the cargo light wires or do I need to go to the fuse for dash lights. Thanks Ken.

 

If you are talking about wiring for adding a fog light switch using Nitori’s SR OEM fog light mod method, I did that last weekend. You have to get that “repair wire” pin for ECU 26. The fog switch basically takes pin 26 to ground when you push the button (ECU logic sees a low signal). Since fog switches also use the switch the upper LED bulb symbol won’t come on due to seeing 0V. The switch manufactures assume you are wiring the switch to a relay and on that case a closed switch would send 12V to the upper LED., but Nitori’s SR OEM fog light mod doesn’t work that way, The ECU sends an different output to pick up the fog light relay (and also illuminates the fog light symbol on your dash display). Here's a link to how I wired my Mictuning Fog light switch:
https://www.tacomaworld.com/threads/nitoris-oem-sr-foglight-mod.451495/page-20#post-23529740

 

I’m not Ken lol, but I happened to be here and can answer your question. The analog meter has a much lower resistance than your high impedence Fluke, the analog meter is probably 10 k to 20k ohms (you can check the resistance across the analog meter with your Fluke). So this is putting the analog meter resistance in parallel with your resistor where you connect it. Fluke impedence/resistance on voltage scale is in the Megaohms range so will have no noticeable impact.

 

Ok that clears it up perfectly!

 

You have a 3rd gen so your wiring should be like mine, see the link in my post above for how to wire to the cargo light connector Illum + and Illum -, this way your LED will dim with the dash dimmer control. Then when you wire up the switch wires later you can figure that part out then (depends on power you need).

 

Thanks Dave. That should give me what I need.

 

@Kens04Taco, I have a couple (likely dumb) questions for you. Bear with me, I'm not an experienced modder and am not familiar/comfortable with electronics.

I'd like to add a couple switches for extra functionality with my truck. Namely, an ABS kill switch and a 4LO TRAC ("yellow wire mod") enable/disable switch. Details on these mods here:
ABS disable: https://www.tacomaworld.com/threads/4lo-trac-abs-kill-switch-why-why-not.257444/#post-6254094
4LO TRAC yellow wire mod: https://www.tacomaworld.com/threads/4lo-trac-abs-kill-switch-why-why-not.257444/#post-6254361

These are the switches I've picked for the mods above. AirOnBoard seems to make switches that most closely resemble OEM components, which is great for a clean factory look.
ABS OFF switch: https://www.aironboard.com/online/p...toyota-oem-replacement-abs-off-new-green.html
TRACTION switch: https://www.aironboard.com/online/push-switch-933ng-12volt-toyota-oem-traction-green.html

The function these switches serve seems to be simple enough. Wire them into an existing circuit, which can then be interrupted on command. My lack of experience with electronics makes me think I'm missing something, which is why I'm posting up here.

These switches are only rated for 3A. Do you think I run the risk of frying the switches? The ABS fuses are 50A (ABS1) and 30A (ABS2), but I'm not sure the ABS OFF switch is wired into the same circuit that sees all that amperage. I'm not sure how much amperage is associated with the yellow wire for the 4LO TRAC mod. I'd like to avoid adding relays, since I'm already well out of my comfort zone.

I'm not sure where/how to connect the switch backlight/illumination wires. I'm also not sure if there's a way to get the switch to illuminate when the circuit is disconnected (vice illuminating when connected). Is there some way to pull this off? Without relays, if possible.

 

Hey @Kens04Taco !
I’m about to build out an independent aux box in the bed of truck.
Is there any pros/cons of wiring it as normally OFF relay with 12V trigger..?

added diagram

 

Hey buddy,

Lets get some more details about what your trying to accomplish.

When you say Aux box do you mean a switch panel to control accessories? A box with cigarette/usb chargers? an Inverter? all of the above?? Do you have one or two batteries? If you have two batteries where is the second located.

Normally open relay configuration (87a closed) is the most common relay used IMO. The pros to using this style of relay to power something is the ability to find a replacement just about everywhere you go. It's on every shelf in every autopart store and many other non automotive exclusive stores. Relays don't fail very often but it's nice to know if you get a blem you can easily replace it. When you give me more details about what you're trying to do we can go further into pro and cons and options

 

Hey buddy,

First off I'd like to apologize for the late response. I must have missed your post and I've been extremely busy. First off I'd like to start by saying I think you know more than you think you know. Just by reading your question I can tell that if you wanted to you could become electrically fluent fairly easily.

If you still are interested I think I might be able to help. Also do you want the short and simple or long detailed response? lol

 

My plans have actually changed a bit since I posted this. I plan on skipping the ABS DISABLE switch, since my available switch slots are running low. I still want to do the 4LO TRAC ("yellow wire mod") switch, using a relay to selectively connect/disconnect the relevant wire.

I'll always opt for more detail over less. Lay it on me.