P0603 2009 Nissan Altima Sedan Code - Engine Control Module Power Supply Circuit
Quick Answer
Battery voltage is supplied to the Engine Control Module (ECM) even when the ignition switch is turned OFF for the ECM memory function of the DTC memory, the air-fuel ratio feedback compensation value memory, the idle air volume learning value memory, etc. Common causes include Loose or poor battery terminal connection, Low battery charge, Faulty Engine Control Module (ECM). Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P0603 2009 Nissan Altima Sedan indicates Engine Control Module Power Supply Circuit.
- Common causes
- Common causes include Loose or poor battery terminal connection, Low battery charge, Faulty Engine Control Module (ECM).
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P0603 2009 Nissan Altima Sedan Description
What are the Possible Causes of the DTC P0603 2009 Nissan Altima Sedan?
- Loose or poor battery terminal connection
- Low battery charge
- Faulty Engine Control Module (ECM)
- ECM power supply circuit is open or shorted
- ECM Outdated Program
How to Fix the DTC P0603 2009 Nissan Altima Sedan?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0603 2009 Nissan Altima Sedan code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about P0603 2009 Nissan Altima Sedan Code
1. What does the OBDII code P0603 mean for a 2009 Nissan Altima?
The P0603 code indicates an issue with the Engine Control Module (ECM) power supply circuit, often related to a loss of Keep Alive Memory (KAM) or ECM internal power.
2. What are common symptoms of the P0603 code in a 2009 Nissan Altima?
Symptoms may include a check engine light, difficulty starting the car, rough idling, poor fuel economy, or intermittent stalling.
3. What causes the P0603 code to appear in a 2009 Nissan Altima?
Common causes include a weak or disconnected battery, faulty ECM, poor wiring connections, corroded battery terminals, or a malfunctioning alternator.
4. Can a weak battery trigger the P0603 code?
Yes, a weak or failing battery can cause the ECM to lose power or memory, triggering the P0603 code.
5. Is the P0603 code in a 2009 Nissan Altima serious?
While the car may still run, the code can indicate underlying electrical or ECM issues that should be addressed to avoid performance problems or potential breakdowns.
6. How do you diagnose the P0603 code on a 2009 Nissan Altima?
Diagnosis involves checking the battery voltage, inspecting battery terminals and wiring, testing the alternator, and scanning the ECM for power or memory retention issues.
7. Can disconnecting the battery cause the P0603 code?
Yes, disconnecting the battery can clear the ECM’s Keep Alive Memory, which may trigger the P0603 code temporarily.
8. How is the P0603 code typically repaired in a 2009 Nissan Altima?
Repairs may include replacing or charging the battery, cleaning or tightening battery connections, repairing damaged wiring, or replacing the ECM if it is faulty.
9. Can a faulty alternator cause the P0603 code?
Yes, a failing alternator may not provide consistent power to the ECM, potentially triggering the P0603 code.
10. Should the ECM be replaced if the P0603 code appears?
The ECM should only be replaced after ruling out simpler issues like battery, wiring, or alternator problems as it is an expensive and complex repair.
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