Jeep Remote Control using a ScanTool OBDLink LX Bluetooth
 

Hi Everyone!
I did a search for this module and only got an old thread (2013) and the lengthy soup "What have you done to your Jeep today" threads.

I was getting ready to build a wireless or bluetooth device that would allow me to unlock my Jeep using my phone, when I found this device...

I know I can use it for all sorts of vehicle diagnostics and other metrics, and I am already sold on that alone. But was wondering if anyone else has used this, and if they could recommend a Jeep app that works with it to lock/unlock doors, and other supported features. I found a YouTube about it here...
But the guy's ride is a Nissan 2014, and mentioned that for other cars you would have to find an app that was compatible.

The reason I want this is because I get in and out of my Jeep several times a day, and the spare keys I have in my wallet fell out. So now I worry that I might lock my keys in the Jeep. So this would save me time and effort at my bench creating an embedded device to do what basically an alarm system does. Now I know that alarm systems usually use OBDII to control features with a vehicle. I figured it would be a pretty easy task with an embedded MPU and some code.

But I see this thing working with this dude's car, and my 1998 Jeep Cherokee Sport 4WD 4.0l in-line 6 has OBDII, so I would think it is possible with her too. But I did some searching and did not find anything related to Jeeps.

Any suggestions? Thanks for your time!!

Sorry to say your Jeep's not sophisticated enough to do this. The computer doesn't control all of the vehicles features like newer ones.

Yeah, I was afraid of that. It seems that vehicles that can use this feature to control lights, door locks, power windows, etc, have a CAN bus system. My Jeep most likely uses a serial connection. This means I will have to tap into the switch control itself and trigger a lock/unlock manually. At least this will be easier than the lights. Back to the drawing board.

ISO 9141-2

If you have a Chrysler, European, or Asian vehicle, this is your protocol. It runs at 10.4 kbps and is asynchronous serial communication.

You'll have to make something yourself, and it's quite involved, but it's possible. You will not use the onboard CCD bus at all. It will be entirely microcontrollers and relays.

Thank you and is that YOUR video? And that is cool but the last thing I want is Google starting my Jeep. :) Nice to know it is possible. That daffy google maps lady would find a way to shut my Jeep off by something she heard on the radio while I shoot down the 202 at 75 MPH. No it would definitely have to be using something I wrote.

Back to the door locks... Alarm systems lock and unlock them with a press of the button, and there is no interface to the door switches themselves, so... if my Jeep doesn't have a Body Control Module, there has to be some sort of control module that handles lights, doors, etc that an alarm plugs into and controls.

Anyway, I already have the device created and programmed. I have to login into it with telnet, authenticate, and then send a complex 48 character string to it to activate a GPIO. Certainly not user-friendly, but it will work. And I can build on it. Who knows... a mounted camera with face recognition that does it all when I walk up to the driver side window. All of this assuming I have my phone on me. If I lock my keys AND my phone in the Jeep, then a link will respond to text message codes. If that fails, who knows... maybe a code morse-coded through flashes of light into the cabin. lol That would suck during a lightning storm. Then maybe sound. Knocks on the window in a code might work.

I just do not have the solid state relay built yet. I will probably use mosfets. I don't want anything mechanical.

Yes, that's me.

Full writeup: http://gunscarstech.com/okgoogle

So based on what you said, you're mostly there and are already using a Pi. for power door locks, you'll just wire two of the relays so they'll lock or unlock the doors. The XJ's door locks are just dumb DPDT Center-off switches that provide power to the solenoids.

Thank you for the switch info!! Are you using mechanical relays or SSR? Or something else solid state? Actually, not using a PI because it seemed heavy for this, although I am considering either a RPI 3 B+ or an Odroid Xu4 for an on board accessories/media server. For the door locks, and other stuff, I will be using an ESP32 paired with an STM32F103. It is a custom module I built for my home automation projects and is very reliable. Redundancy and watch dog code to make sure they are always ready, and sleep configurations to parasite very little power in standby. I haven't had a failure (yet) with any of my home indoor or outdoor projects. I'll use the on board server to talk to the modules using MQTT, but will still be able to access each module with my phone via wifi or bluetooth.