Shop Parts keyboard_double_arrow_right
Need car parts? Select your vehicle
Reading Time: 4 minutes
Summary
  • DTC P0603 stands for “Internal Control Module Keep Alive Memory (KAM) Error.” It’s logged when the KAM fails its self-test.
  • A dead battery, an outdated PCM software, a malfunctioning PCM, and charging system issues are some of the issues that could trigger the P0603 code.
  • Some symptoms of this trouble code include an activated check engine light, the engine stalling, and an illuminated ABS or traction control light.

The power control module (PCM) is an essential part of your vehicle system. For starters, it’s in charge of controlling and monitoring several systems in your engine. But just like any other component, the PCM may also encounter some issues over time.

The P0603 code is an engine trouble code related to an issue with the Internal Control Module Keep Alive Memory (KAM). Read on to learn more about KAM and the P0603 code.

What Does the P0603 Code Mean?

Diagnostic trouble code (DTC) P0603 stands for “Internal Control Module Keep Alive Memory (KAM) Error.” It is logged once the PCM fails its KAM self-test.  The code is triggered when the result of the self-test calculations are not as expected.

To understand the code better, let’s talk about computer memory and storage. Computers have two types of memory: ROM and RAM.

See also  P0171 Code: System Too Lean (Bank 1)

Read-only memory (ROM) refers to the permanent memory stored in your vehicle’s computer. This data cannot be changed and will remain as it is even if your PCM loses power.

nissan engine control module
P0603 code is logged once the PCM fails its KAM self-test.  The code is triggered when the result of the self-test calculations are not as expected.

Random-access memory (RAM) refers to the temporary memory that is stored in the PCM. This is where your PCM stores new data. RAM memory can be categorised as volatile or nonvolatile.

Nonvolatile RAM memory will be retained even if you disconnect your car battery. However, data stored in a volatile RAM memory will be lost once you turn off the ignition. Keep alive memory (KAM) is a type of volatile RAM memory that can be wired straight to the battery so that its data won’t be erased when you turn off the ignition.

KAM is crucial because it stores data regarding drive cycles. This memory constantly changes based on driving and sensor inputs. The PCM regularly runs a routine self-check to monitor the performance of the KAM modules. Once the PCM perceives that the results of the mathematical calculations during self-tests are not what’s expected, it will trigger the P0603 code.

You can learn more about vehicles’ computers in our brief discussion about the ECM/PCM’s RAM.

Note: The definition of code P0603 may be different depending on the vehicle manufacturer. Consult the appropriate repair manual or repair database for the exact code definition.

What are the Possible Causes of the P0603 Code?

Here are the possible triggers of a P0603 code:

  • Dead battery
  • Wiring and/or connection issues in the PCM’s power or ground circuit
  • PCM software in need of an update
  • Faulty PCM
  • Charging system issues
See also  P0193 Code: Fuel Rail Pressure Sensor “A” Circuit High

What are the Common Symptoms of a P0603 Code?

Here are some of the common symptoms related to a P0603 code:

How to Diagnose the P0603 Code

engine control unit
Diagnosing a P0603 code isn’t easy. There are several factors that may cause the issue, so it may be hard to identify which component is causing the problem.

Diagnosing a P0603 code isn’t easy. There are several factors that may cause the issue, so it may be hard to identify which component is causing the problem. For instance, you’ll have to identify if it’s caused by a faulty PCM or an issue with the PCM itself. If you don’t have enough experience with auto repair, it’s best to take your vehicle to an auto repair shop and have a mechanic do the diagnostic procedures for you.

However, if you prefer to diagnose this code yourself, we recommend consulting vehicle repair manuals or online repair databases.

How to Fix the P0603 Code

P0603 is a generic trouble code, which means it may appear on various makes and models. However, even if this code is generic, there is no universal solution for all vehicles. For example, repair steps that worked for a P0603 on a Nissan Altima may not work for a P0603 on a Ford F-350.

If you don’t have enough experience and tools to get the job done, we suggest taking your vehicle to an auto repair shop for proper diagnosis and repair. However, if you decide to fix this code yourself, we recommend consulting a vehicle-specific repair manual or subscribing to an online repair database.

See also  P0123 Code: Throttle / Pedal Position Sensor "A" Circuit High

Where to Get a Replacement Battery

In addition to triggering DTC P0603, a dead battery also prevents your vehicle from starting and causes your engine to stall. This can leave you stranded at the worst possible time. To avoid this, it’s best to replace your vehicle’s faulty battery as soon as you can. Thankfully, CarParts.com has your back.

Here at CarParts.com, we want to enable you to order online with confidence. That’s what our customer-centered guarantees are for. Our price-match guarantee ensures that you’re always getting the best deals when you shop with us. If you find a CarParts.com-listed product on a competitor site for cheaper, let us know. We’ll be happy to meet or beat their price on the spot. We also have a lifetime replacement guarantee for our loyal customers. The battery you order from us can be sent back at the end of its lifetime, and we’ll issue you a refund for your next purchase on our site.

Don’t get stuck in the middle of nowhere. Resolve DTC P0603 by purchasing a new battery at CarParts.com today.

About The Authors
Written By Automotive and Tech Writers

The CarParts.com Research Team is composed of experienced automotive and tech writers working with (ASE)-certified automobile technicians and automotive journalists to bring up-to-date, helpful information to car owners in the US. Guided by CarParts.com's thorough editorial process, our team strives to produce guides and resources DIYers and casual car owners can trust.

Reviewed By Technical Reviewer at CarParts.com

Richard McCuistian has worked for nearly 50 years in the automotive field as a professional technician, an instructor, and a freelance automotive writer for Motor Age, ACtion magazine, Power Stroke Registry, and others. Richard is ASE certified for more than 30 years in 10 categories, including L1 Advanced Engine Performance and Light Vehicle Diesel.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.

File Under : OBD-II Trouble Codes Tagged With :
Aries Fender Flare Light Kit Rebate
Subscribe
Notify of
guest
0 Comments
Inline Feedbacks
View all comments
expand_more
CarParts.com Answers BE PART OF OUR COMMUNITY: Share your knowledge & help fellow drivers Join Now
The owner of this website has made a commitment to accessibility and inclusion, please report any problems that you encounter using the contact form on this website. This site uses the WP ADA Compliance Check plugin to enhance accessibility.