Attempting to extend the range of key fob remote

[Billy K]

To each their own I guess.
Do you carry and use a cellphone everyday by chance?

I agree with BrokeYota, and you actually. I do not want another subscription to anything, and yes I carry a cell phone at all times, regrettably.

Most software used to be buy it and it's yours. Update when you want to. Lately, every company wants to do the "cloud" subscription BS to get you to pay $$ every year. Example: My 2008 Rubicon navigation still works with no subscription, EVER! Sure the maps could be updated for new roads, but it works for me. Yes I AM old. But if people keep paying the yearly stuff, they will never change their model and keep taking your $$. I know the TOY app counts on a cell connection and costs some dough. But a few bytes of "texting" your truck is negligible on the network these days. Meaning it should not cost TOY $hit to run this service.

Then there is the privacy issue. Get prepared. It will get worse. Again, I am OLD, I hate the "cloud" knowing where I am am, what I eat, and where I shop. You can turn off such things, if you think to do so. The "GOV" will be able to shut off your vehicle on a subpoena, or less , in the near future. Look up "social credits" in China if you want to see how they handle those who do not conform. Then maybe call up MADMAX on YouTube. That is your future.

I might actually use the Toy app if it did not cost so much. @TOY, lower cost = more subscribers = more $$ for you, perhaps.

Either way, the range on the key-fob is crap, and the sequence to press to start is crap also. Do they test with real people before they commit to the software?

Disclaimer: I am an EE engineer who designs real products, and I have had a couple of beverages before writing this comment. Please hold the flames to low heat.

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[BrokeYota]

I agree with BrokeYota, and you actually. I do not want another subscription to anything, and yes I carry a cell phone at all times, regrettably.

Most software used to be buy it and it's yours. Update when you want to. Lately, every company wants to do the "cloud" subscription BS to get you to pay $$ every year. Example: My 2008 Rubicon navigation still works with no subscription, EVER! Sure the maps could be updated for new roads, but it works for me. Yes I AM old. But if people keep paying the yearly stuff, they will never change their model and keep taking your $$. I know the TOY app counts on a cell connection and costs some dough. But a few bytes of "texting" your truck is negligible on the network these days. Meaning it should not cost TOY $hit to run this service.

Then there is the privacy issue. Get prepared. It will get worse. Again, I am OLD, I hate the "cloud" knowing where I am am, what I eat, and where I shop. You can turn off such things, if you think to do so. The "GOV" will be able to shut off your vehicle on a subpoena, or less , in the near future. Look up "social credits" in China if you want to see how they handle those who do not conform. Then maybe call up MADMAX on YouTube. That is your future.

I might actually use the Toy app if it did not cost so much. @TOY, lower cost = more subscribers = more $$ for you, perhaps.

Either way, the range on the key-fob is crap, and the sequence to press to start is crap also. Do they test with real people before they commit to the software?

Disclaimer: I am an EE engineer who designs real products, and I have had a couple of beverages before writing this comment. Please hold the flames to low heat.

 

[TrustButVerify]

I was super stoked to find out that my 2025 SR Model has a remote start, but the range is PATHETIC. I found the antenna module behind the plastics behind the driver-rear seat and soldered a wire onto the antenna. I ran the wire up the rear pillar and all the way across the top of the rear window. I've seen other people make similar modifications with very impressive results. I got two or three times the range out of it, but IMO, it's still barely acceptable. I'm going to continue to try to find other ways to improve it and I'll post here if I come up with anything.

This is the antenna module. It's behind the rear seat on the driver side. The plastics just pull away and the only tools you need is a 10mm socket to remove the module. You need to remove the corner and the back one on the driver's side.

Here's a close-up of the module removed.

This is what it looks like under the cover. The silver thing shaped like a messed up rectangle is the antenna.

I drilled a hole in the cover for the wire to go through. I drilled mine too high at first

I soldered a thin (20ga maybe) wire to the antenna. The wire ended up being about 7' long.

Put the cover back on and reinstall the module.

I ran the wire up the rear pillar, under the plastic and then under the ceiling panel across the rear window to the passenger side. I taped the end of the wire just to make sure it doesn't ground on the body, but I don't know if that was necessary at all.

How did you arrive at the length of the antenna? You generally want a multiple of the frequency. Like 1/2, 1/4, 5/8etc. To calculate resonant frequency, you take 468/f and that gives you the frequency that a wire length of x is resonant on.

So a 7' antenna would resonate at 66.5Mhz, which is well beyond what's necessary. It's actually going to pick up other harmonics, like 132, 198, 264, 330 etc. I have no idea what other services use those frequencies, but you run the risk of unintentionally picking up radio signals you don't want coming into your key fob receiver.

If you find out the frequency the fob uses, just look to make an antenna that is a multiple of that. Not a radio person, but if you measure the total length of the antenna in the box, and knew the frequency you could devise an appropriate length antenna for that.

Remotely mounting the box elsewhere or with an external antenna appropriately sized might work better.

Edit: Per Google, not AI, 315mhz is the frequency. So a full wavelength is about 35" and a half wave of that would be 17.8" I have no clue what type of antenna that, how it's polarized, or anything else, since I only remember this vague from many years ago.

 

[Billy K]

How did you arrive at the length of the antenna? You generally want a multiple of the frequency. Like 1/2, 1/4, 5/8etc. To calculate resonant frequency, you take 468/f and that gives you the frequency that a wire length of x is resonant on.

So a 7' antenna would resonate at 66.5Mhz, which is well beyond what's necessary. It's actually going to pick up other harmonics, like 132, 198, 264, 330 etc. I have no idea what other services use those frequencies, but you run the risk of unintentionally picking up radio signals you don't want coming into your key fob receiver.

If you find out the frequency the fob uses, just look to make an antenna that is a multiple of that. Not a radio person, but if you measure the total length of the antenna in the box, and knew the frequency you could devise an appropriate length antenna for that.

Remotely mounting the box elsewhere or with an external antenna appropriately sized might work better.

Edit: Per Google, not AI, 315mhz is the frequency. So a full wavelength is about 35" and a half wave of that would be 17.8" I have no clue what type of antenna that, how it's polarized, or anything else, since I only remember this vague from many years ago.

Yes that! And then you are adding to the existing antenna in the device, which is tuned to the PCBA receiver, and matched to its impedance. It would most likely be better to remove the internal antenna, then run a thin coax cable up to the rear window (or outside on the roof) and attach a small antenna sized for that (approximate) frequency. Or for that matter, use the original removed antenna. I'm not an RF engineer and RF can be very tricky, but probably no harm in trying different lengths of "antenna" on this module.

Also I am not sure, but this may be a 2-way communication. Key fob to truck and truck to key fob. Can anyone confirm this?

Or --- Maybe extend the wire harness and move the existing module up near the rear window? If you try this you should try to use the same types and sizes of wires. I presume part of it may be CAN bus and will be a 120 Ohm twisted pair.

 

[BrokeYota]

How did you arrive at the length of the antenna? You generally want a multiple of the frequency. Like 1/2, 1/4, 5/8etc. To calculate resonant frequency, you take 468/f and that gives you the frequency that a wire length of x is resonant on.

So a 7' antenna would resonate at 66.5Mhz, which is well beyond what's necessary. It's actually going to pick up other harmonics, like 132, 198, 264, 330 etc. I have no idea what other services use those frequencies, but you run the risk of unintentionally picking up radio signals you don't want coming into your key fob receiver.

If you find out the frequency the fob uses, just look to make an antenna that is a multiple of that. Not a radio person, but if you measure the total length of the antenna in the box, and knew the frequency you could devise an appropriate length antenna for that.

Remotely mounting the box elsewhere or with an external antenna appropriately sized might work better.

Edit: Per Google, not AI, 315mhz is the frequency. So a full wavelength is about 35" and a half wave of that would be 17.8" I have no clue what type of antenna that, how it's polarized, or anything else, since I only remember this vague from many years ago.

I thought the same thing when I was first looking into it, but my research showed it didn't actually matter with this kind of antenna and the fact that I modified the receive side.

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