P0603 on Nissan
Internal Control Module Keep Alive Memory (KAM) Error
P0603 on Nissan vehicles indicates internal control module keep alive memory (kam) error. Au7o has documented this code across 1 Nissan model — most commonly on Frontier. This code means the engine computer's keep-alive memory (KAM), which stores learned adaptive values and settings between key cycles, has failed an internal check. The PCM relies on this memory to retain fuel trims, idle learning, and other adaptations. A KAM error can cause rough running, poor fuel economy, or transmission shift issues until the module relearns or is repaired. Typical repair costs on Nissan range from $150 to $900, depending on the specific model and root cause.
Common Causes of P0603
- •Loss of constant battery power to the PCM (blown fuse, bad connection)
- •Weak or failing battery
- •Corroded or loose battery/ground connections
- •Recent battery disconnection without relearn
- •Internal PCM fault
- •Damaged PCM power/ground wiring
P0603 on Nissan by Model
Nissan Frontier(1 issue)
- Intermittent No-Start or Stall from Faulty Start/Stop Logic and ECM Software2022-2024
Owners of the new-generation Frontier have reported intermittent no-start events, extended crank, or occasional stalling tied to control-module logic, battery state sensitivity, or software calibration issues. Complaints commonly describe the truck acting like a weak battery or failing to restart normally despite the battery testing good. Nissan has issued service information and software-related fixes for some starting and drivability complaints on this platform.
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View P0603 across all makes →Frequently Asked Questions
What does P0603 mean on Nissan?▼
P0603 stands for "Internal Control Module Keep Alive Memory (KAM) Error." This code means the engine computer's keep-alive memory (KAM), which stores learned adaptive values and settings between key cycles, has failed an internal check. The PCM relies on this memory to retain fuel trims, idle learning, and other adaptations. A KAM error can cause rough running, poor fuel economy, or transmission shift issues until the module relearns or is repaired. On Nissan specifically, this code is documented across 1 model.
What causes P0603 on Nissan vehicles?▼
Common causes on Nissan: Loss of constant battery power to the PCM (blown fuse, bad connection), Weak or failing battery, Corroded or loose battery/ground connections, Recent battery disconnection without relearn, Internal PCM fault. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0603 on a Nissan?▼
Repair costs on Nissan range from $150 to $900, depending on the specific model and root cause.
Which Nissan models have P0603 documented?▼
Au7o has documented P0603 on 1 Nissan model: Frontier.