Error Codes P0231 and P0603

[shane0917]

P0231 Fuel Pump Relay Driver Circuit Failure

P0603 Internal Control Module KAM Error

I borrowed a friends Edge Programmer and it gave me these codes. I had no reason to check for a code (no lights on dash) Trucks seems to be running fine. First powerstroke though so I'm not sure. 180K miles on it gets pretty bad gas mileage. 11-12 MPG it's 4x4 185 tires. Could these codes cause my gas mileage to be bad? Is there something I need to check into more? Or should I just clear the codes. Thanks in advance for all the help.

[SCUFFY828]

i have seen a p0231 when fuel pump is gone or going out ,might just want to run fuel pressure test to verify operating o.k., p0603 , could have been set when you connected programmer or somebody else has removed one , if truck runs fine ,would clear codes and drive until gives you a reason to pull codes again

[shane0917]

Says fuel pump secondary circuit low. Is there a primary curcuit? What does this mean exactly. Do I need a new fuel pump? How much should that run me. Is it a drop the fuel tank thing or is it somewhere I can change it?

[SCUFFY828]

there is a primary circuit , would not be concerned which circuit , fuel pump is on frame rail , like i said ,if fuel pressure is good you might want to clear codes and disregard at ths time ,but it can mean fuel pump is going out

[ivan_stephens]

did you fix the problem, i have the same codes but my truck will not start
can you please call or email me
thanks ivan
254-681-1009

[shane0917]

Ivan I only had the codes when I checked them I just cleared them and they didn't come back. If your truck won't start and you have the same code I would think it is prob. your fuel pump. One of the techs can prob. help you better. You will need to post your truck year mileage and anything else about your truck they might need to know.

[SCUFFY828]

ivan pull the fuel filter cap and see if any fuel in the bowl ,then cycle the key and see if it tries to fill up fuel bowl, just a quick way to see if pump is doing anything

[CarTotem]

I have that code and my truck will run very good at idle for 45 min, then shut down like I turned the key off. Then it will give me big problems starting again, if it starts at all. I'm going to swap out the fuel pump and see what the result is.

Patrick