MR3T-14F642-AA keyless theft module

[Trace]

Backstory- my TPMS module quit reading my tire sensors so I had the local Ford dealer mobile service truck come out today. He found this module plugged in to the system and the jumper cable that comes from it to the OBD port is faulty.

This isn't causing the TPMS problem. But the tech has never seen one of these modules so he didn't know what it was. We Googled to see.

My questions- what does it do? And can I get a replacement jumper cable to go from the module to the OBD port position? The tech said it's only about 8 inches long.

Thanks in advance

Sponsored

 

[Skye]

I see a Ford module with a cable attached.

The module is your GateWay Module (GWM). The GWM acts as a network hub or switch, linking the different network segments of the vehicle together. If the GWM is faulty or fails completely, the four or five segments involved cannot communicate.

Attached is a diagram showing how the GWM links the network segments together. The CAN, or Controller Area Network, of the car.

One side of the GWM is what you hock up to when you want to talk to the car, the On-Board Diagnostics (OBD) port. The other side is the CAN bus.

If you follow from the GWM through the MS-CAN (Medium Speed Controller Area Network), you'll see one terminating module is the Radio Transceiver Module (RTM). The RTM receives the radio signals from the TPMS sensors in the wheels, then sends that data to the Body Control Module (BCM) and ultimately, your screen, the Instrument Panel Cluster (IPC).

The GWM is a very common module. I wouldn't be surprised if Ford uses the same one in multiple models. Should be an easy locate, ship and buy.

Edit,

Notice "Smart Dat Link Connector" in the labeling on your photo. And "DLC" in the diagram. I don't see any text about it being a keyless theft module. But...

The RTM not only receives TPMS signals, it also receives Radio Frequency signals from your key fob. Intelligent Access. If the RTM is faulty or cannot communicate with other modules correctly, not only will TPMS fail, but the fob might not work either.

If the tech was referring to a "keyless theft module", that's really more the RTM; it's directly involved with access and the fob. The GWM is just a switch or hub.

 

[Trace]

I read everything you wrote in both messages. I don't think there's a GPS tracker in the car but I'm not certain.

I understood the tech to say that there was a jumper cable coming from the module to the OBD port location. He said the jumper was defective. It had no data and no power at the port.

He unplugged it and plugged directly into (something) and was able to get into the computer. He told me I need a new jumper...

 

[Skye]

He unplugged it and plugged directly into (something) and was able to get into the computer. He told me I need a new jumper...

Ya, sorry about that. I'd deleted that other post, but somehow, I think that suspicion might be right.

I went out and looked at my 22 Mach.

The OBD port is by the Driver's left knee, just under the dash. On RH drive cars, it'd be the Driver's right knee.

My DLC/GWM is bolted to the metal framing of the dash. The OBD port is vacant and facing me. The backside of the GWM is the CAN and a harness, going up into the dash and later throughout the car.

What's interesting to me in your photo is the use of tie wraps, the GWM is not bolted to the dash and there's a port/cable directly beneath it. My car does not have any of that.

My thinking is the dealer installed a GPS tracker (aka keyless theft module), in-line with the OBD port (for power).

Maybe the dealer was done and turned off that tracker or canceled its service. Maybe something broke. IDK. That's not unusual. We've had a few threads of the same: a feature stops working, people go to the OBD to pull codes and find this gizmo (different types and models).

Different trackers. Different connections and methods.

If you bought the car from a dealer nearby and they are still there, I'd go have a sit-down with them and confirm my suspicions. You deserve a car with the bits installed as they were from the factory. Given the feel of that discussion, you could allow them to remove it and return to as it should be, or go somewhere else.

If bought from like Carvana or a distant location, I'd leave as-is for now, but seek out someone to check everything I'm saying.

It doesn't seem like the car has been damaged. It just seems that this extra device is interfering and needs to be removed. Additional threads below. It's a situation that is more and more common. Some in the 7G forum have found them as well.

https://www.google.com/search?q=mus...HQKLJYIQrQIoAnoECBoQAw&biw=1463&bih=741&dpr=2

Edit,

And if the selling dealer sold some type of "tracking service" for your security, discuss that with them. Some dealers sell things like this. I wouldn't put it past a few they piggyback off it to recover cars if the payments stop.

 

[Trace]

I bought the car from a private individual.

The service tech said I could leave it as is, just that the next person needing the data port would have to unhook the jumper pigtail like he did.

He thinks this is all that is wrong. IDK

 

[Trace]

Turns out you are right. I Googled the numbers on the silver tag. It's a Lojack number. I know a guy who can remove it.

Apparently not part of my TPMS issue though.

 

[Skye]

Apparently not part of my TPMS issue though.

So you've got a way ahead on the GPS/LoJack. What's up with TPMS?

 

[Trace]

He couldn't say. He diagnosed it when he found the data port and reprogrammed it. And said it was working.

I have 4 new FoMoCo wheel sensors because I got another set of wheels, he said they may not have been recognized by the car. But they worked for a few weeks...

 

[Skye]

I have 4 new FoMoCo wheel sensors because I got another set of wheels, he said they may not have been recognized by the car. But they worked for a few weeks...

I think it's best to focus on one thing at a time.

Jumper cables, additional accessories, etc., are changing electrical resistances and loads on the GWM and possibly the buses involved.

The DLC/GWM is a pathway for everything, from OBD connectivity to TPMS and all other modules in-between. I'd get the area of the jumper, Lo Jack and all that situated first, then return to TPMS.

The Ford OEM TPMS units have been auto-sensing for the last few years. Driving for a bit, away from other modules on the same frequency, is often all that's required.

Once the LoJack has been removed and that area returned to normal, I'd be interested to see how TPMS acted on the next drive.

 

[5doorsoffury]

i hope this goes to people "lojack" style trackers are garbage. imho put a lot of apple air tags in the car and get a old iPhone you leave in the car to hit the air tags non stop. leave the phone on when you want it "armed" lol

ill say the obd 2 port is the first thing i check since its easy access to hs/ms can and i rip out. anything that's there will interfere with the remote starters i used to install. most lazy installs can be found there and by behind the left foot panel

if i was a crook all i had to do is open the door look underneath, notice that isn't a oem obd2. if it looks aftermarket then i have 2 options.. option 1 yank it out with a hard swift idgaf pull or look carefully and unplug it.

real lojack is in a headliner or jammed in a weird location. oem loking wire harnesses traverse with other ones. the real deal lojack installers open the oem harness to hide the wires inside and reassemble them. i had to remove one once and o.m.g.it took all day... that techs install was a masterpiece! normally i get mad when they make it hard to remove but that time i was honored to remove it lolol

 

[Trace]

I figure I have 2 options. Unplug it and leave it there, or contact LoJack and put it in my name. I don't feel the need to pull it out if it's disconnected.

Sponsored