AutoCodes – Nissan – P0603 2005 Nissan Pathfinder

P0603 2005 Nissan Pathfinder 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 2005 Nissan Pathfinder 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.

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Code Popularity 2,723

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 14, 2020

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0603 2005 Nissan Pathfinder Description

OBDII Code P0603 2005 Nissan Pathfinder - Engine Control Module Power Supply Circuit - AutoCodes.com — P0603 2005 Nissan Pathfinder Code - Engine Control Module Power Supply Circuit

What does this mean?

What are the Possible Causes of the DTC P0603 2005 Nissan Pathfinder?

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ECM Outdated Program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 2005 Nissan Pathfinder?

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.

What does this mean?

Code Tech Notes

Start by charging the vehicles battery and clean terminal, once the battery is charged and the terminals are clean and secure, erase code. If the code comes back ON you may have to reprogram or replaced ECM

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0603 2005 Nissan Pathfinder 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.

Need more information about the P0603 2005 Nissan Pathfinder code?

Need more information on how to fix the P0603 2005 Nissan Pathfinder code? Get Access to Factory Service Manuals

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0603 2005 Nissan Pathfinder Code

1. What does the OBDII code P0603 mean for a 2005 Nissan Pathfinder?

The P0603 code indicates an issue with the Engine Control Module (ECM) power supply circuit, often caused by a loss of voltage to the ECM or an internal ECM fault.

2. What are the common symptoms of code P0603 in a 2005 Nissan Pathfinder?

Symptoms may include the check engine light turning on, poor engine performance, stalling, or difficulty starting the vehicle.

3. What causes the P0603 code to appear on a 2005 Nissan Pathfinder?

Common causes include a weak or disconnected battery, faulty ECM, poor wiring connections, or issues with the ignition switch or power supply relay.

4. Can a dead battery trigger the P0603 code?

Yes, a weak or recently disconnected battery can disrupt the ECM's memory, leading to the P0603 code.

5. How do you diagnose the P0603 code in a 2005 Nissan Pathfinder?

Start by checking the battery voltage, inspecting wiring and connectors to the ECM, and testing the ignition switch and power supply relay for proper function.

6. Can the P0603 code cause drivability problems?

Yes, it can cause intermittent issues such as stalling, hesitation, or poor engine performance, depending on the severity of the power supply problem.

7. Is it safe to drive a 2005 Nissan Pathfinder with a P0603 code?

While the vehicle may still be drivable, ignoring the P0603 code can lead to further issues, including potential ECM damage or unexpected stalling.

8. How is the P0603 code fixed on a 2005 Nissan Pathfinder?

Repairs may involve recharging or replacing the battery, repairing or replacing damaged wiring, inspecting the power supply relay, or replacing the ECM if necessary.

9. Can resetting the ECM clear the P0603 code?

Resetting the ECM may temporarily clear the code, but the underlying issue must be addressed to prevent the code from returning.

10. How much does it cost to repair a P0603 code on a 2005 Nissan Pathfinder?

Costs vary depending on the cause, ranging from $50 for a battery repair to $1,000 or more for ECM replacement. Accurate diagnosis is key to estimating repair costs.