The Smart Key That Was, Then Wasn't, Then Was?

Michael Mobile Technician Clinton, Utah Posted   Latest  
Case Study
Collision
Security
2019 Ford F-150 Lariat 3.5L (4) 10-spd (10R80)
No Crank / No Start

Got a call to a body shop this week. They had a 2019 Ford F150 that they had removed a door on and after the Proximity key would not be recognized. Even when placed in the programming / emergency pocket the key would not trigger the vehicle to start. So I am going to go through the steps I took. I am not sure which ones cured this vehicle or if it was a combination of steps.

The first thing I did was interview the technician and gather information. His story was that they removed the passenger door and windshield. The vehicle had to be moved to another station. In an attempt to start the vehicle, there was a message on the cluster. "No Key Detected". After some research, they found the programming pocket and put the key in it. Still no start. The door locks worked. The alarm would set from remote.

We reconnected the passenger door and pushed the latch to the locked position. The hood was open so we pushed down the hood latch so the hood was seen as closed. Working through service information I deducted that the vehicle was in lockout mode. I asked the technicians if the alarm had gone off. They said yes and they disconnected the battery to not have to hear the alarm. To get out of lockout, I first tried to use the keypad on the door frame. It made no difference. The vehicle has remote start. I attempted to remote start, no go. I then went through the procedure of setting off the alarm. To get rid of the horn honking, I removed the relay. After the alarm had gone for 4.5 minutes, I opened the driver's door. After 10 minutes the hazard lamps quit flashing. I pushed the start button. No Key Detected. This process was repeated three times. Then out of frustration I pushed the remote start. The vehicle started. Unfortunately when I pushed the start button on the dashboard, No Key Detected. The vehicle would not shut off and would not go into gear. After about 10 minutes of running, the truck shut off.

In further questioning the technician, I found that they had replaced the restraint control module. I asked if they could have missed plugging in the antenna in the center console. They removed the panels to reveal the antenna connected. We placed the key next to the antenna. No Go. In earlier testing I had previously located the key in the back seat of the truck and it would not start. This time I placed the proximity key on the backrest of the back seat. The truck started. I then brought the key to the driver seat. The vehicle started. I am not sure what kind of whacked out strategy that Ford uses on these vehicles. The Smart Key system seems to get real angry when you take parts off. I believe removing the battery cable when the alarm was tripped is what caused the system to shut down. Regardless, it is working now.

+2
Interesting
Hollis Technician
Boulder, Colorado
Hollis Default
 

Having fun and getting paid, now that's how ya do it :O)

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Gary Owner/Technician
Buena Vista, Colorado
Gary Default
 

I am not sure what kind of whacked out strategy that Ford uses on these vehicles. Sounds like this is becoming the order of the day for diagnostic techs.... {:0(

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Glen Owner/Technician
Arthur, Illinois
Glen Default
 

Any codes in the BCM? Did the transmitter ID's in the BCM and RTM match?

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Michael Mobile Technician
Clinton, Utah
Michael Default
 

Glen, The strange part about this one is that there were no security related codes stored relating to keys. Until the remote start function worked only a handful of modules communicated when the emergency flashers were going. When I was able to communicate with RTM, it showed two keys programmed. No keys were re-programmed during the time I was working on the vehicle. It seemed that the inside…

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Hollis Technician
Boulder, Colorado
Hollis Default
 

Any chance some of these systems 'Time-Out' after numerous attempts in a given or short time period ? Thought I had read this somewhere, can't find it in my library.

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Michael Mobile Technician
Clinton, Utah
Michael Default
 

Hollis, Very possible. I had wondered about the battery saver feature and the door being off leaving the overhead lamps on.

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Hollis Technician
Boulder, Colorado
Hollis Default
 

My assumptions are that there are only so many possible DTC's, enabling and code setting scenarios that are programmed into the logic that the CM's can process, leave a sensor out of the loop, a misstep in the sequencing, a command or input at the wrong time while the left hand doesn't know what the right hand is doing and by the time you back off to reassess the CM regains its wherewithal, so…

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Anthony Technical Support Specialist
Kirkwood, Pennsylvania
Anthony Default
 

Hi Mike: Some disjointed thoughts, if you don't mind. But first, this: 1: Disclaimer 1: I know nothing about this vehicle. Take everything that I'm about to write with a grain o'salt. 2: Disclaimer 2: What I am about to write should not be construed as an indictment or me stating that you did something correctly or incorrectly. I have no way of knowing since I wasn't there. 3: My post is…

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Michael Mobile Technician
Clinton, Utah
Michael Default
 

Guido, Not sure what went on there but when the dash does not light up. Thinking back I did scan all possible modules and not all modules reported due to no ign feed. I had to manually enter the tear tag to id the vehicle. After the remote start activated, there was communication with all modules. The codes were only ones that would have been associated with the collision. Front RS…

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Anthony Technical Support Specialist
Kirkwood, Pennsylvania
Anthony Default
 

Hi Mike: One of my points was that the BCM could cause the issue but not in a way that many are familiar with. The only other thing that comes to mind is an after-market programming (of some sort) being installed. Guido

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