Programmed FOB, but key won't start vehicle

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There is a bit of art to it, admittedly. You need to be quick with the key swap and hitting "ok" in Techstream, whatever that sequence is.
With the original key in, as soon as it pops up to say 20 seconds, 19 seconds, it says disconnected, start over. I am assuming that OBD2 should be plugged in under the steering wheel and to the right, and not somewhere under the hood. I've tried a few USB ports, they all connect and get me through everything up until I do the utility for the new transmitter code. It scans, then gives the message to put in new key, then immediately says disconnected, start again.

Any ideas guys?
 
With the original key in, as soon as it pops up to say 20 seconds, 19 seconds, it says disconnected, start over. I am assuming that OBD2 should be plugged in under the steering wheel and to the right, and not somewhere under the hood. I've tried a few USB ports, they all connect and get me through everything up until I do the utility for the new transmitter code. It scans, then gives the message to put in new key, then immediately says disconnected, start again.

Any ideas guys?

In techstream, can you verify how many keys are registered? The system is a bit cryptic, so perhaps the behavior you see is what happens when you have already reached the max limit of keys. Explore the menus a bit and see what you can find out.

FWIW, my techstream worked to program my 06LX immobilizer, but not the keyless entry. Tried over and over and over. No luck. I tried the manual method with door opening and closing and such. Worked second time. Perhaps you're seeing something similar and need to try to manual method a few more times.
 
Is there a writeup on how to program with techstream? Got a new key today and would rather use that then the door open work around.
Techstream walks you through pretty clearly. If you can connect via Techstream, all the instructions will be on screen once you select the immobilizer menu.
 
In techstream, can you verify how many keys are registered? The system is a bit cryptic, so perhaps the behavior you see is what happens when you have already reached the max limit of keys. Explore the menus a bit and see what you can find out.

FWIW, my techstream worked to program my 06LX immobilizer, but not the keyless entry. Tried over and over and over. No luck. I tried the manual method with door opening and closing and such. Worked second time. Perhaps you're seeing something similar and need to try to manual method a few more times.
From what I can tell, there is 1 out of 5 currently.
 
I found the trick is the timing of key removal and then (IIRC) hitting OK in Techstream. It took me a few tries to be fast enough, then I did a lil' dance when I got it right.
 
If trying to add the remote using this method doesn't work I would say you need to delete remotes.
 
Alright, got somewhere, probably not good though. I see a trouble code B2795, unmatched key. I suspect that's why I can't program a new one. Any idea how to get around this?

I saw this post from @cruiserdan "
Apr 11, 2004

If you DO NOT HAVE an existing master key YOU MUST replace the engine ECU, PERIOD. THERE IS NO WAY AROUND IT. If you loose the existing valet your rig will only travel with the aid of a tow truck, PERIOD.

The ECU is around 1600 bucks. There is a plain master, the part number ecsapes me at the moment, that a 100 of that vintage will accept without having to buy one of the 250 dollar jobs with the keyless entry buttons on it. BUT YOU STILL NEEED AN ORIGINAL MASTER TO ACCESS THE PROGRAMMING MODE, NO EXCEPTIONS, PERIOD."

So, I am guessing that the key that I have is the valet key, not the master key. That's why the programming isn't working. Eek...
 
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Alright, got somewhere, probably not good though. I see a trouble code B2795, unmatched key. I suspect that's why I can't program a new one. Any idea how to get around this?

I saw this post from @cruiserdan "
Apr 11, 2004

If you DO NOT HAVE an existing master key YOU MUST replace the engine ECU, PERIOD. THERE IS NO WAY AROUND IT. If you loose the existing valet your rig will only travel with the aid of a tow truck, PERIOD.

The ECU is around 1600 bucks. There is a plain master, the part number ecsapes me at the moment, that a 100 of that vintage will accept without having to buy one of the 250 dollar jobs with the keyless entry buttons on it. BUT YOU STILL NEEED AN ORIGINAL MASTER TO ACCESS THE PROGRAMMING MODE, NO EXCEPTIONS, PERIOD."

So, I am guessing that the key that I have is the valet key, not the master key. That's why the programming isn't working. Eek...

At the time I posted that everything I said was accurate. Moving forward 16 years a good locksmith can now break into the ECU and get it into the programming mode. Yes, you pay for the service or you learn to be a professional locksmith.
 
At the time I posted that everything I said was accurate. Moving forward 16 years a good locksmith can now break into the ECU and get it into the programming mode. Yes, you pay for the service or you learn to be a professional locksmith.
I found the Locksmith Charley in AZ, then looked and found one locally. So I'll give them a call in the morning. I'm glad that it's easier now, pricey, but better than thinking that I will have locksmith skills anytime soon. Thanks as always @cruiserdan
 
What year is your truck?
 
You are trying to code a 2nd key, correct? Has it ever been programmed to any other vehicle before? The key you have and works is for sure a master key?

I do recall that @Mauser is the guru when it comes to ensuring the security device in the key matches your MY. I read many of his posts to ensure I got the correct blank key for my rig. It may be worth a bit of searching on his posts to compare his advice to the security device in your new key. Hope this helps.

You're more than welcome to come to Orlando and I can try and help. I can't guarantee success though ... I'll give it my best shot.

Btw that unrecognized key error code gets stored when you try and start the rig with an unprogrammed key. Blow away the code.
 
I do recall that @Mauser is the guru when it comes to ensuring the security device in the key matches your MY. I read many of his posts to ensure I got the correct blank key for my rig. It may be worth a bit of searching on his posts to compare his advice to the security device in your new key.
☝🏾This. IIRC from reading Mauser’s thread months ago, if you get the wrong blank, nothing you do will make it work.
 
I don't have an ecu to swap out right now, but will put this here.

Will flash for food.

I do have plenty of programmed chips if you can remove and replace a surface mounted chip.
 
I don't have an ecu to swap out right now, but will put this here.

Will flash for food.

I do have plenty of programmed chips if you can remove and replace a surface mounted chip.
That is an awesome thing that you are doing during these times. Greatly appreciated.

So, I found a locksmith here locally who will flash the ECU. He also said that there is a new solution whereby he can completely duplicate the valet key. So, I am going to go that route as it is significantly cheaper.
 
That is an awesome thing that you are doing during these times. Greatly appreciated.

So, I found a locksmith here locally who will flash the ECU. He also said that there is a new solution whereby he can completely duplicate the valet key. So, I am going to go that route as it is significantly cheaper.

Cool. Just out of curiosity what does he charge to flash the computer?
 
Cool. Just out of curiosity what does he charge to flash the computer?
He wanted $300 to flash or $200 to make 2 duplicate valet keys. Pricey. If I had time, I would have taken it out and sent it to you :-)

I suppose the keys are like most key cards for building security, they are easily duplicated with simple devices that are readily available online.
 

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