MIL code P0523 - Engine Oil Pressure Sensor

When my check engine light came on I hooked up the tool to see what code I would get. This is the code I'm getting which indicates a problem with the engine oil pressure sensor/switch circuit high voltage.

Question 1: is this a simple fix and about how much do you think this would cost at a Jiffy Lube or Walmart type place?

I'm also concerned because the MIL is no longer on. I'm wondering if I could have cleared it off using the tool. This morning the engine light was no longer lit and my oil pressure guage is reading no pressure at all now.

Question 2: could it be possible to have no pressure? or like the code indicates it's just a matter of the sensor not reading the pressure?

Question 3: is it safe to operate the vehicle? I'm not going to have any money in my budget for at least another month.

Thank you.

Post the year and engine type

2008 K1500 4x4 Silverado crew LT
8-5.3L

2008 K1500 4x4 Silverado crew LT
8-5.3L

most likely the wiring or the sensor is bad . this code is saying voltage/pressure way to high. I would check the wiring to it. it may have a damaged wire. then replace the sensor.

you have a 2008 5.3L ENGINE . have you read the manual for this on what type oil to use ? you best use the correct GM spec oil this engine has many issues !