P2138 & P0653 Error Codes

[Huntsvillian]

Hi,
I have a 2012 1500 5.7L with 105k miles. I don't drive it very much, in fact less than 1000 miles on the last 6 months. Went into town today and got a P0653 & P2138 code. I've attached images of the errors. Managed to make it home. Checked and obviously seen it is a throttle body error code that can mean accelerator pedal sensor, wiring, dirty throttle body and PCM issues. We got a ton of rain this past weekend, and the temperature went up today. I was away but the truck was parked. I'm good with checking the throttle body and plan to later tonight once we've had dinner.
So some questions if anyone can help.

1. Where do I start with troubleshooting?
2. If I'm checking the continuity of the wiring to the throttle body is the other end located at the back of the accelerator?
3. Is there a way to check the PCM?

Thanks.

 

[04fxdwgi]

Other end is connected to the ECM on both items. ECM takes input signal from pedal and translates that to an output signal to the throttle body.

Check all your wiring and connections between the three.

 

[Huntsvillian]

Other end is connected to the ECM on both items. ECM takes input signal from pedal and translates that to an output signal to the throttle body.

Check all your wiring and connections between the three.

Maybe a silly question but can this be related to a bad battery? I only ask as I honestly just remembered after reading your reply......a few months back the truck wouldn't start. I suspected the battery as it was low and the volt sign came up. Took it in to get checked, and they charged it up and said it was borderline okay. Truck has started fine since but wondering if there is a bad cell.

 

[04fxdwgi]

Very possibly a battery problem. Ram's don't like marginal batteries.