Limp mode + 11(!) CEL codes

[ILTTG]

Driving on the highway yesterday when the check engine light and electronic throttle control lights turned on and the car went into limp mode. Shortly after, both lights started blinking and the car started running very roughly with even less power. It also started to making a clicking sound that rises in frequency with RPM. Fortunately, I was pretty close to home so I managed to make it to my driveway. I read the codes with a code reader and this is what I got:

P0304 - Cylinder #4 Misfire
P0562 - System Voltage Low
P0652 - Sensor Reference Voltage “B” Circuit Low
P1628 - Module Ignition Supply Input Malfunction
P2104 - Throttle Actuator Ctrl Sys-Forced Idle
P2106 - Throttle Actuator Ctrl Sys-Forced Limited Power
P2100 - Throttle Actuator Ctrl Motor Circ/Open
P2127 Throttle/Pedal Pos Sensor/Switch E Circ Low Input
P2282 Air Leak Between Throttle Body and Intake Valves
P0316 Misfire Detected On Startup (First 1000 Revolutions)
P2282 Air Leak Between Throttle Body and Intake Valves
(2282 showed up twice for some reason)

Some of these sound related to the limp mode, but it seems like there's some electrical issue causing problems with the ETC. The only other time I've ever had the ETC light turn on was when I had the battery unplugged for a week while some body work was done; it went away the next time I started the car. I did have to replace the battery last week, as I hadn't driven the car in three months and it was dead. I pulled the new battery yesterday and the voltage was 12.73, which seems normal. The new battery is a Duralast Gold 34-DLG.

Does anyone have any ideas on what might be going on? I am hesitant to take it to one of the Dodge dealerships here both because they are inept and notorious for throwing in new parts without knowing what is actually going on - I live in a ****ty city and have had bad experiences.

Thanks.

Edit: Some of these code descriptions may be wrong, I got them off the net and am finding multiple listings for some. Those are the codes I read, though.

 

[ViperJohn]

If you reset all the codes, does the car come out of limp mode? What year is your car, approximate miles, etc?

 

[ILTTG]

2008, 35k miles.

I unplugged the battery for a little while (about five minutes) while I checked the connections and the battery ground; when I plugged it back in and started it back up, it ran normally for a few seconds, then kicked back into limp mode with those codes. I was considering leaving it unplugged for longer than that.

Something else I forgot to mention: when I turn the key but don't start the car, the gauges light up and the yellow light under the "10" in the battery gauge turns on. I don't recall it doing this before.

 

[EZ 2B Green]

A couple of scenarios that would fit the symptoms is a failed alternator and/or a bad battery. My guess, based on what you have shared here is that you were running the car from battery power when the voltage finally dropped low enough for the computer to start getting bad data and throwing codes. The low voltage light on your gauge says your battery is very low. It also could be that your battery is sulfated and will no longer hold a charge. If its a bad battery and the alternator is maxing out trying to charge it, you may damage the alternator by driving the car. See if you can confirm or deny either of these failures first. Good Luck!