P0490 GMC Code - Exhaust Gas Recirculation Motor Control Circuit High Voltage
Quick Answer
The Engine Control Module (ECM) supplies the Exhaust Gas Recirculation (EGR) valve with a 5 V reference circuit, a low reference circuit, an H-bridge motor directional control circuit, and a signal circuit. Common causes include Faulty Exhaust Gas Recirculation (EGR) Valve, Exhaust Gas Recirculation Valve harness is open or shorted, Exhaust Gas Recirculation Valve circuit poor electrical connection. 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
- P0490 GMC indicates Exhaust Gas Recirculation Motor Control Circuit High Voltage.
- Common causes
- Common causes include Faulty Exhaust Gas Recirculation (EGR) Valve, Exhaust Gas Recirculation Valve harness is open or shorted, Exhaust Gas Recirculation Valve circuit poor electrical connection.
- 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 P0490 GMC Description
What are the Possible Causes of the DTC P0490 GMC?
- Faulty Exhaust Gas Recirculation (EGR) Valve
- Exhaust Gas Recirculation Valve harness is open or shorted
- Exhaust Gas Recirculation Valve circuit poor electrical connection
- Faulty Engine Control Module (ECM)
How to Fix the DTC P0490 GMC?
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 is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0490 GMC 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 P0490 GMC code?
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Need Help with the Code?
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Information for Specific GMC Models
- P0490 2014 GMC Sierra — Exhaust Gas Recirculation Motor Control Circuit High Voltage
- P0490 2015 GMC Sierra — Exhaust Gas Recirculation Motor Control Circuit High Voltage
- P0490 2016 GMC Sierra — Exhaust Gas Recirculation Motor Control Circuit High Voltage
- P0490 2017 GMC Sierra — Exhaust Gas Recirculation Motor Control Circuit High Voltage
- P0490 2018 GMC Sierra — Exhaust Gas Recirculation Motor Control Circuit High Voltage
Frequently Asked Questions about P0490 GMC Code
1. What are the common symptoms of OBDII code P0490 GMC?
The common symptoms of code P0490 include engine hesitation, rough idling, decreased fuel efficiency, and the illumination of the Check Engine Light.
2. What causes the Exhaust Gas Recirculation (EGR) Motor Control Circuit High Voltage issue?
The EGR motor control circuit high voltage issue is often caused by a faulty EGR valve, damaged wiring or connectors, or a malfunctioning EGR control module.
3. How can I diagnose the OBDII code P0490 GMC?
Diagnosing code P0490 involves using a diagnostic scanner to retrieve the trouble code, checking the EGR valve and related components for physical damage, and testing the electrical connections for proper voltage.
4. Can a dirty EGR valve cause code P0490 to trigger?
Yes, a dirty or clogged EGR valve can disrupt the proper functioning of the EGR system and potentially lead to code P0490 being triggered due to high voltage in the motor control circuit.
5. Is it safe to continue driving with OBDII code P0490 GMC active?
It is not recommended to continue driving with code P0490 active, as it can lead to further engine damage and decreased performance over time. It's best to address the issue promptly.
6. How can I repair the Exhaust Gas Recirculation Motor Control Circuit High Voltage problem?
Repairing code P0490 typically involves cleaning or replacing the EGR valve, checking and repairing any damaged wiring or connectors, and resetting the trouble code with a diagnostic scanner.
7. Can a DIY enthusiast fix OBDII code P0490 GMC at home?
Yes, depending on your skill level and access to tools, it is possible to address code P0490 at home by following repair guides, but if in doubt, it's advisable to seek professional help.
8. What are the potential long-term effects of ignoring code P0490?
Ignoring code P0490 can lead to increased emissions, reduced engine efficiency, and potential damage to other engine components over time, ultimately resulting in more costly repairs.
9. How much does it typically cost to fix OBDII code P0490 GMC at a repair shop?
The cost of fixing code P0490 can vary depending on the extent of the issue and the labor rates of the repair shop, but it can range from $100 to $500 or more, including parts and labor.
10. Will resetting the trouble code make OBDII code P0490 GMC go away permanently?
Simply resetting the trouble code without addressing the underlying issue will not make code P0490 go away permanently. It is essential to diagnose and repair the root cause to prevent the code from reoccurring.
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