I have a 2010 6.7 mega cab. I bought I used and it only came with one key fob. When I go too start it sometimes it cranks right away sometimes you turn the key and nothing happens . the radio comes on but wont crank over so you turn it off and it will start. sometimes it takes several times to get it to start.

 

My first thought is the one key fob you have is not being read by the ECU every time. I would get another one programmed and only use that one to see if that is the problem.

 

they have a known issue with the wireless module (ignition switch). mine has done it from day 1. very hit and miss but i cycle the key and it works.

 

My truck has done the same thing. Try replacing the batteries in the FOBIK. I've notice my keys behave differently when the batteries start getting weak. I thought there was a TSB for the ignition module, but it may have been for the key popping out.

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if i remember right the tsb was for the module not releasing the key when shutting truck off and removing key from module.

 

I don't know why a smiley showed for the TSB number- needed a space after the 8.
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Close. I just looked it up. It was for the key releasing in any gear but park. TSB (K08 ) mentioned the WIN module requires replacement if the FOBIK can be removed in neutral... something about running through the check about 50 times and if it comes out in neutral, replace the WIN module.

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