P0603 is the internal control module keep alive memory error. Start by charging the battery and clean the terminals, once the battery is charged and the terminals are clean, erase the code. If the code comes back on you may have to reprogram or replace the PCM.
Trouble code P0603 means: Powertrain Control Module Keep Alive Memory (KAM) Error
how do i fix a dtc code 42 in a 1995 chev 6.5 diesel?
It's an O2 sensor code
Trouble code P1693 means: A companion DTC was set in both the ECM and PCM
http://www.aa1car.com/library/ford_lean_codes.htm
usually that code is a hose off or cracked
A P200C DTC is a Diesel Particulate Filter overheating issue for the newer trucks that are conforming to the new 2010 emissions standards.
* P0521 Engine Oil Pressure Sensor/Switch Circuit Range/Performance
Trouble code P1131 means: Lack Of HO2S11 Switches - Sensor Indicates Lean
Trouble code P1131 means: Lack Of HO2S11 Switches - Sensor Indicates Lean
Usually, replace the spark plugs and/or the #2 ignition coil.
P1693 : Dtc detected in the companion module. You need to check the Ecm and Pcm for codes. Which ever did not have p1693 will have a code.