I have a 06 3500. 148k. I got to work the other day. Pulled up and went to exit the vehicle to clock in and the alarm started going off. The alarm is factory I have 2 sentry keys if this matters but either way the only way to get the truck to stop was to shut it down. Right when the engine cut off the alarm stopped. I tried to restart the truck and nothing. Tried getting out closing the door and locking and unlocking both with the buttons on the key and physically inserting the key in in the keyhole. Wouldn't start. Went to work and came back on break and the truck would give me half of a crank but not enough to start. Checking the batteries connection and all were clean. I checked the batteries with a meter and they both tested 12.4 volts. Went back to work. Went to leave work normally at the end of the day and low and behold the truck fired up like the previous 8hrs never even happened. Any explanation would be appreciated because I don't want the truck to leave me stranded somewhere or a long tow.


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Put it in neutral and try,
olny thing i can think of to try.