Electrical smart guys

[DaveB]

I have the LED bar working fine in the new Titan, but I hate the look of the switch. So I ordered an extra factory fog light switch; PN 25370-1PA0A. It comes with no pin numbers or any other telltale signs, so I used my trusty ohm meter to try to figure out which pins are the switch. Well...none of them! I thought maybe the switch was faulty, so I tried it in place of my factory fog light switch and it works. Very confusing that NONE of the pins (there are 4) seem to go to zero ohms in any switch position. I'm not a rocket scientist, but I'm reasonably sure 2 of the pins will be a ground and a dash light feed, the other two should be a switch....but no combination of probing with the ohm meter shows either....Any ideas?

Edit: the pins are tiny things....not wide blades like an aftermarket switch. The factory wiring to the stock fog-light switch is quite small....leads me to think that the switch has an LED bulb inside and likely "talks" to a computer or BCM...but I dunno. I have a relay in my LED set-up...so the amperage going through the switch is very minimal.

 

[neilsleder]

You check multiple pins at the same time. Maybe it uses 2 pins for positive and two for negative? I hate electricity!

 

[TylerG]

I'm guessing you're probably right in that it plugs into a harness that talks to the computer via a CANBUS or something of the likes.

 

[whoDEANie]

What kind of resistance are you getting with your ohm meter? Is there an LED indicator on the switch when you activated it?

My guess is that two pins are for the dash light which will likely be an LED. If so, probing the wires with your ohmmeter will show an open circuit one way and close to a short if you swap the positive and negative test leads. That would leave the second set of pins tied to the poles of the switch but may also have a diode or LED indicator in series. If so, probing the leads forward and reverse should yield an open one way and a short the other with the switch closed.

 

[DaveB]

What kind of resistance are you getting with your ohm meter? Is there an LED indicator on the switch when you activated it?

My guess is that two pins are for the dash light which will likely be an LED. If so, probing the wires with your ohmmeter will show an open circuit one way and close to a short if you swap the positive and negative test leads. That would leave the second set of pins tied to the poles of the switch but may also have a diode or LED indicator in series. If so, probing the leads forward and reverse should yield an open one way and a short the other with the switch closed.

I tried multiple ohm settings and every pin combo/switch position both ways several times (beers) and the meter always indicates open circuit. I may try putting power to one pin at a time, then use the voltage meter as a ground....? Like you said, if there's an LED or a diode (or both) it might work one way and not the other....

 

[Vance Matheson]

Does your meter have the diode symbol next to the ohms setting on your meter?. Have to put a voltage through the diode positive to negagtive.

 

[whoDEANie]

Googled Tundra fog light switch pinout and found this. Don't know if it's correct or not.

 

[DaveB]

The switch above is how every other switch I've used works.....the ohm meter with tell you which 2 are the switch real quick.

 

[arff]

My guess, 2.75 to 3.25 pulse voltage to a module(computer)

If trying with voltage don't go over 5 volts.

 

[neilsleder]

Did you try hook the red and black wire together?

 

[Tchetek]

Check your working factory fog light switch for volts dc to ground at the harness. Could be a solid state switch and could require an actual load on it to switch rather than a mechanical contact. Or get the wiring diagram for the truck!

 

[tex78]

And it needs more than a test light for a load


Lots of new light and trailer modules need enough load to work and send power out

New led light might not draw enough power




Quit being Mr cool pants, wire in a gay old school switch and relay and run it old school

 

[DaveB]

And it needs more than a test light for a load


Lots of new light and trailer modules need enough load to work and send power out

New led light might not draw enough power




Quit being Mr cool pants, wire in a gay old school switch and relay and run it old school

I have an ugly switch in there now....I may just try to find a nicer looking old-school switch....

 

[TylerG]

I have an ugly switch in there now....I may just try to find a nicer looking old-school switch....

what about a UTV style switch Dave? TONNES of options for them on Amazon, lighted, non lighted, all sorts!

 

[DaveB]

what about a UTV style switch Dave? TONNES of options for them on Amazon, lighted, non lighted, all sorts!

That's what is there....it fits the knockout hole, but sticks out compared to the factory switches

 

[vodoo103]

Gregg distributors has tons of different styles. Was able to find some simple, discreet switches that blend into the dash of my Silver-Aydo.

 

[vrscr43]

Is that the Diesel Titan or the gasser?

 

[DaveB]

Is that the Diesel Titan or the gasser?

Gasser. New diesel seems to be having issues. This 5.6 motor in mine has been used in the Infinity line for a couple of years...great power.

 

[vrscr43]

I am thinking of getting the same truck, gasser as well.
Heard the diesel has issues.
Nice rig!

 

[woody_tobius_jr]

I ran my power through my high beams and got a remote relay for my bars. I can either have them on with my high beams or shut them off so it's just my high beams...no need to run wires and switches into the cab of your truck. It is just a small 4 button remote ( similar to a car starter remote) I'm very happy with the results.