I had mine come on after leaving my radio on for a few hours, then starting the Ram
WITH OUT first turning the key to the OFF position
I was told that doing this can cause the lightning bolt to come on, i drove it for a couple thousand miles after it did
This is taken from another website
Take it to the dealer if it has not cleared when restarted.
7. Electronic Throttle Control (ETC) Light
This light informs you of a problem with the Electronic Throttle Control (ETC) system. The light will come on when the ignition is first turned ON and remain on briefly as a bulb check. If the light does not come on during starting, have the system checked by an authorized dealer.
If a problem is detected, the light will come on while the engine is running. Cycle the ignition key when the vehicle has completely stopped and the shift lever is placed in the PARK position, the light should turn off. If the light remains lit with the engine running, your vehicle will usually be drivable; however, see an authorized dealer for service as soon as possible.
If the light is flashing when the engine is running, immediate service is required and you may experience reduced performance, an elevated/rough idle or engine stall and your vehicle may require towing. For vehicles equipped with a premium cluster this indicator will display in the Electronic Vehicle Information Center (EVIC). Refer to ”Electronic Vehicle Information Center (EVIC) — If Equipped” in this section for more information. UNDERSTANDING YOUR INSTRUMENT PANEL 219
I had this issue. I would start the truck, it would run fine for a while and then all of a sudden the lightning bolt would start flashing and the truck would go into limp mode. I tried checking connectors, replacing the accelerator pedel, cleaning the throttle body, nothing worked. I tried to pin down the conditions that made it happen and thought it was mostly when the weather was hot, and would happen every 3rd time I started the truck.
It eventually got worse to the point where it was dangerous to drive, so I brought it to the dealer. They first replaced the PCM under warrenty, that didn't solve the problem, so I brought it back...turns out there was a faulty wire in the wiring harness (I believe leading from the accelerator pedel to the PCM). They replaced the wire and it was as good as new. cost me about $700 though
I would say you really need to have a dealer look at this and do thier diagnostics. Otherwise you are just taking a shot in the dark, like I was.