P1840 2016 Chevrolet Silverado Code - Internal Mode Switch 'S' Circuit Low Voltage
Quick Answer
The diagnostic trouble code P1840 for a 2016 Chevrolet Silverado indicates an issue with the Internal Mode Switch 'S' Circuit Low Voltage. Common causes include Faulty Internal Mode Switch, Damaged wiring or connectors in the 'S' circuit, Malfunctioning transmission control module. 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
- P1840 2016 Chevrolet Silverado indicates Internal Mode Switch 'S' Circuit Low Voltage.
- Common causes
- Common causes include Faulty Internal Mode Switch, Damaged wiring or connectors in the 'S' circuit, Malfunctioning transmission control module.
- 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 P1840 2016 Chevrolet Silverado Description
The diagnostic trouble code P1840 for a 2016 Chevrolet Silverado indicates an issue with the Internal Mode Switch 'S' Circuit Low Voltage. The Internal Mode Switch (IMS) is a component of the vehicle's transmission system that helps control the transmission shift points and ensures smooth operation. In this case, the 'S' circuit refers to a specific electrical circuit within the IMS that is experiencing low voltage, which can lead to various performance issues.
Common Causes of P1840 2016 Chevrolet Silverado
- Faulty Internal Mode Switch
- Damaged wiring or connectors in the 'S' circuit
- Malfunctioning transmission control module
- Issues with the vehicle's power supply or ground connections
Symptoms of P1840 2016 Chevrolet Silverado
- Erratic shifting patterns
- Difficulty changing gears
- Transmission slipping
- Limp mode activation
- Poor acceleration and decreased fuel efficiency
How to Fix P1840 2016 Chevrolet Silverado
- Perform a thorough diagnostic scan to retrieve the trouble code and pinpoint the exact cause of the low voltage in the IMS 'S' circuit.
- Inspect the Internal Mode Switch and associated wiring for any signs of damage or wear. Replace the IMS if necessary.
- Check and repair any damaged wiring or connectors in the 'S' circuit to ensure proper electrical connections.
- Test the transmission control module and related components to verify their functionality. Replace any faulty components as needed.
- Clear the trouble code from the vehicle's system memory and perform a test drive to ensure the transmission operates smoothly.
Cost to Fix P1840 2016 Chevrolet Silverado
The typical repair costs for addressing the Internal Mode Switch 'S' Circuit Low Voltage issue in a 2016 Chevrolet Silverado can vary depending on the specific cause of the problem and the required repairs. Generally, the cost of replacing the Internal Mode Switch and associated components can range from $200 to $500, including parts and labor. Keep in mind that diagnostic time and labor rates at auto repair shops can vary, with hourly rates typically ranging between $80 and $150. It's advisable to consult with a trusted mechanic or dealership to obtain a more accurate estimate based on your location and vehicle specifics.
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Frequently Asked Questions about P1840 2016 Chevrolet Silverado Code
What does the OBDII code P1840 mean on a 2016 Chevrolet Silverado?
The P1840 code indicates an issue with the Internal Mode Switch (IMS) 'S' circuit, specifically low voltage detected by the transmission control module (TCM).
What are the common symptoms of the P1840 code in a 2016 Chevrolet Silverado?
Symptoms may include the Check Engine Light being illuminated, erratic or hard shifting, transmission stuck in one gear, or a failure to engage gears properly.
What causes the P1840 code to appear on a 2016 Chevrolet Silverado?
Common causes include a faulty Internal Mode Switch, wiring issues such as damaged or corroded connectors, a malfunctioning transmission control module, or low transmission fluid.
How can I diagnose the P1840 code on my 2016 Chevrolet Silverado?
Diagnose the issue by scanning for codes, inspecting IMS wiring and connectors for damage or corrosion, checking transmission fluid levels, and testing the IMS circuit with a multimeter.
Can I drive my 2016 Chevrolet Silverado with a P1840 code?
While it might be possible to drive, it is not recommended as the issue can lead to further transmission damage or unsafe driving conditions due to gear engagement problems.
How do I fix the P1840 code on a 2016 Chevrolet Silverado?
Repairs may include replacing the Internal Mode Switch, repairing or replacing damaged wiring or connectors, refilling or flushing transmission fluid, or reprogramming the TCM if necessary.
How much does it cost to repair a P1840 code on a 2016 Chevrolet Silverado?
The cost varies depending on the repair but can range from $150 to $400 for diagnostics and IMS replacement, with additional costs for wiring repairs or TCM programming.
Can a low battery voltage cause the P1840 code in a 2016 Chevrolet Silverado?
Yes, low battery voltage can cause improper TCM operation and trigger the P1840 code, so ensure the battery and charging system are functioning correctly.
Is the P1840 code specific to Chevrolet Silverado trucks?
No, the P1840 code can appear on other vehicles with similar drivetrain systems, but the details of the repair may vary by make and model.
How can I prevent the P1840 code from reoccurring on my 2016 Chevrolet Silverado?
Regularly inspect and maintain the transmission system, ensure proper fluid levels, and address wiring or electrical issues promptly to prevent future occurrences.
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