Push to start not working. Any ideas??

[CFCSW6]

Hey everyone. I have a 2019 longhorn. Got in yesterday and pushed the start button. Nothing. No start, no ignition on, no accessories, no reaction to pushing the button.
background on me, I’m a former mercedes master tech so I checked the obvious.
Keys good. Battery good. Truck starts and runs with remote start. Push to start button lights up in general. Checked through fuse designation but not seeing any fuse/circuit failure that would cause it not to work but still illuminate. All signs point to the switch.
got a new switch from the dealer, nothing.
hoping someone here has an idea before towing to the dealer. If anyone has a wiring diagram to share I would be grateful. Not finding much online.

 

[djevox]

Did you check to see if there were any codes?

 

[CFCSW6]

Did you check to see if there were any codes?

I don’t have a scanner. Can you scan for codes if you can’t turn on the ignition?

 

[Sascwatch]

Does the truck shut off using the push to start button? If so I don’t think it’s your issue. Try pressing the push to start button with your key fob, roadside assistance told me this would allow you to start even with a dead fob.

If it were a fob issue I’d think it would display a “key fob not present” message when attempting to start.

Could be one of those awesome anti theft things dealers like to install preventing it from doing anything aswell.

 

[CFCSW6]

Does the truck shut off using the push to start button? If so I don’t think it’s your issue. Try pressing the push to start button with your key fob, roadside assistance told me this would allow you to start even with a dead fob.

If it were a fob issue I’d think it would display a “key fob not present” message when attempting to start.

Could be one of those awesome anti theft things dealers like to install preventing it from doing anything aswell.

No. There is no response from the push to start button. If I start with remote start, I have to turn off with remote start (button on the key). I have both keys. They work normally lock, unlock, remote start.
Of course remote start is great but it starts the car but doesn’t turn on “accessories”. ie can’t drive the truck, put in gear etc.

 

[CFCSW6]

No. There is no response from the push to start button. If I start with remote start, I have to turn off with remote start (button on the key). I have both keys. They work normally lock, unlock, remote start.
Of course remote start is great but it starts the car but doesn’t turn on “accessories”. ie can’t drive the truck, put in gear etc.

And yes. I tried the push the button with the key. This is for a dead key fob.

 

[Sascwatch]

Starting with remote start would rule out any sort of check engine light/code as that is one of the checks it does in order for it to work.

When started remotely you should see the run light flashing on the push to start button, you are NOT required to push the brake to actually put the truck into run (when started remotely) so that would rule out a brake pedal switch. Definitely looking like an issue with the push to start button or it’s wiring.

 

[CFCSW6]

Starting with remote start would rule out any sort of check engine light/code as that is one of the checks it does in order for it to work.

When started remotely you should see the run light flashing on the push to start button, you are NOT required to push the brake to actually put the truck into run (when started remotely) so that would rule out a brake pedal switch. Definitely looking like an issue with the push to start button or it’s wiring.

Thanks. That confirms a few things. And with trying a replacement switch I’ve ruled that out too.
I doubting but not ruling out a wiring issue. Had a quick poke around and saw nothing abnormal (water or critters )
Any info on what the push to start switch reports to? Is there an ignition module? Anyone know where that is located?
I will start tracing wiring but it’s currently raining sideways outside and I’m not climbing under the dash right now.

 

[Sascwatch]

There’s so many modules and computers in these trucks I wouldn’t be surprised there’s one just for the push to start button.

I’d take a look under the panel below your steering wheel for anything that looks aftermarket or not factory installed, there has been a lot of owners reporting dealer installed anti-theft crap on newer vehicles for “inventory control” even if you pay cash. Two small screws at the bottom of the panel and then give it a good pull, there’s several clips that hold it on really well. Might even be a blown fuse for the ignition switch? These devices tend to tie into the OBD port behind that panel with an inline piggyback connection.

 

[CFCSW6]

To update: I had a faulty RF hub module.

 

[MurphBigHorn]

To update: I had a faulty RF hub module.

How did you figure it out?

 

[CFCSW6]

How did you figure it out?

The dealer. And it took them a week…

 

[adam434]

The dealer. And it took them a week…

Do you happen to have a part number mine is doing the exact same thing as of this morning.

 

[Hamesie]

Do you happen to have a part number mine is doing the exact same thing as of this morning.

If it happens again, here is a video that is extremely informational on the issue.