Causes and Fixes P0603 Code: Internal Control Module Keep Alive Memory (KAM) Error

How to fix a P0603 engine code: Internal Control Module Keep Alive Memory (KAM) Error
A P0603 code is set once the PCM/ECM fails its KAM self-test.
Read-only Memory (ROM): Data Not lost when power is removed.
Random-access memory (RAM): Data Is lost when power is removed.
Information that changes, such as drive cycles, cam, or crank learn, is stored in RAM.
Nonvolatile RAM memory will be retained even if you disconnect your car battery. However, data stored in a volatile (KAM) RAM memory will be lost once you turn off the ignition.
Possible Causes of a P0603 Code:
Dead Battery
Charging System Problems
Wiring Issues / Blown Fuse
Faulty PCM/ECM
By using this information user assumes all risk of use.
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[@joshgall253]

I have a 04 F250 6.0. I noticed my alternator power cable was grounding to the alternator itself. burnt the insulation wrap and pretty much welded to the alternator. Replaced the alternator and shrink wrapped the power cable as well as cleaned the exposed wire as best i could. Truck cranks but no start. batteries are new as well as alternator. Could the alternator power cable that is still (what looks burnt or dark cable wire before i wrapped it) be the cause of my no start or PCM. I as got the P0603 code.

[@HVAC_Mechanic]

When the power shorts out it can cause a lot of issues and be problematic to fix sometimes, since a lot of components can be damaged. Usually, a fuse or relay is blown, but sometimes, it can also damage the computers or wiring. I would start by getting a schematic and check all the fuses and relays. There should be a big main fuse in the fuse box, along with fusible links.

[@Az-elite]

I have a 08 Infiniti FX35 with u1000 and p0603 code. Tried figuring it out for months. What would your theory be about what's wrong with the car ? Bad ecu or wiring ? Battery has been good all this time and starter work bc car cranks but no start.

[@youngestdoinit]

Literally got the same car 08 with the same code

[@nhsplayer07]

@@youngestdoinitsame did you figure out why? Mine was dead for a while and got the code when I restarted the car the battery is like 2 years old tho.

[@williambrown629]

I have a 2007 Infiniti g35x and my odometer and my radio and heat are not working the blower stay on I’m thinking the ecu is fried but I don’t trust a shop and I can replace it myself

[@nehemiahgandy2973]

Ever find the problem??

Does this lead to a P1639 code?

[@Angel-r6n]

Bad battery 9 out 10 times

My 2008 F350, 6.4 has thrown code P1639