Tow Haul light not working

Recently purchased 2013 Tundra with Tow Package. Tow/Haul light does not come on when I turn on the key and does not light when I push Tow/Haul button. Build sheet and VIN verify truck has Tow/Haul. Any ideas besides a trip to the dealer?
Thanks,

 

Check for potential fuse issue, always a good first step if just one component is not working and other systems are normal.

 

Is the switch plugged in? Asking the easy questions....

 

Does the truck respond differently in Tow/Haul mode? By the seat of your pants, does it feel like it’s working when you press the button while driving?

 

I checked the fuses but I'm going to continuity check again this evening. I tried hook up to a trailer to check signal lights but still no Tow/Haul light. No difference in response when pressing button and I even tried holding the button down but still no light on dash. Still, thanks for the ideas!!

 

All the fuses related to towing checked good. No difference in response. Any other ideas out there?

 

Have you checked to be sure that the button is connected on the backside?

 

Hard to reach but I'm working on the button suggestion. Here is a photo of my main fuse box. Where is #44? All other fuses are good.

 

That little cubby hole that's just below the T/H switch, if you can stuff a couple fingers in there and press them away from each other horizontally, then pull toward you, usually you can get that panel out.

 

WOW, You da' man! That was it. How the button ever became unplugged will puzzle me for the rest of my normal life...but just a little bit.
Thanks

 

Score!
The previous owner may have had the panel out for some reason and it didn't get reconnected by accident. I've done it myself...

 

I've done that myself before...thanks for the tip on getting to it.

 

Thanks for posting photo. I have no experience with this type of fuse but i think it's good.

 

What fuse..looking at red circle?

 

The fuse was a suggestion from one of the other members. To tell the truth I am not familiar with that type of larger fuse. You may try to contact the member who posted the photo. Anyone else???

 

Don't forget the indication in the dash cluster. I was under the impression from his reply that the switch was simply disconnected from the harness in the dash.

 

My interpretation from his replies is that the switch was left unplugged from a prior dash disassembly and that reconnecting it resolved the issue and that his further comments about the fuse is merely a tangent.

 

Does anyone have wire diagram for tow haul mode switch? Found out I am not getting no power..believe it should be 9.5V

I have 2015 Toyota Tundra 5.7l double Cab

 

I have 4 wires plugs into switch..the wire diagram showing only two

 

They could be for backlighting/illumination.

 

Is green and red power?

 

I think that those are momentary switches and may not work the way we assume a switch normally works. That's also why they reset when we turn the truck off and then restart. They just close for a moment and communicate to the ECU to use a different shift pattern.

Can you offer a little more background on how your determination that you don't have power came to be? Was it working before? Was there unrelated under the dash work done recently? Those kinds of things, what was going on before this discovery.

 

I discover my tow haul light speedometer cluster didn't light up and no change..I change OEM new switch and ECM. Still having issues. I knew I wasn't getting 9.5V from switch. I compare to my other switch next to tow haul switch TSV getting 9.5V light indicator on dash. ..I believe it maybe electric issues. It stop working about a week ago. I am trying to figure out where fuses,wires, and what module control. Any information will help. Thanks

 

So if I have this right:

-One day you noticed that when you pressed the Tow/Haul button, nothing happened, no change in the shifting of the truck and the indicator in the dash cluster did not come on. Was there any work done under the dash just before this? Does the switch itself still light up when you turn on the headlamps?

-You replaced the switch itself and some ECM. What ECM? As far as I know the engine and transmission are all in the same ECU "box" mounted in the passenger side of the firewall. You replaced that?

-Sorry, I don't know what "TSV" is, or just haven't had enough coffee so far to have a blinding flash of the obvious.

-I don't ever recall reading about or seeing any fuses dedicated to just Tow/Haul functions.

 

Yes correct! After I replaced the ECM on passenger firewall and reprogram it nothing changed. I put the old ECM back since it wasn't issues. No truck has not been work on before..tow haul was working great 2 weeks ago when I was pulling RV camper. I relise tow haul mode wasn't working, no light speedometer cluster or change transmission when I press switch. The light on tow haul switch does come on when I turn headlight. Do you know if there fuse? Sorry I was perfering traction control switch..do you know switch suppose to have 9.5v or 12v?

 

There may be a fuse that serves that circuit and isn't labeled as such, I fear that you'd pretty much have to use a meter and individually check each and every fuse one at a time to determine that. I don't know off the top of my head what voltages might be found at the switch, I may be able to pop the switch out of the dash on my truck at some point today and put a meter on it though.

 

Please let me know what volts asap. Thank you for your time

 

Where is AJ4 19 and Junction connection located at on wire diagram?