The P1759 trouble code is a diagnostic trouble code (DTC) that indicates a malfunction related to the front brake solenoid valve function in automatic transmission systems, particularly in Nissan and Infiniti vehicles. This code is significant as it can lead to various transmission issues, including erratic shifting and loss of power, which can severely affect vehicle performance. Understanding the implications of this code, its symptoms, causes, and solutions is essential for vehicle owners and DIY mechanics.

P1759 Code Meaning	P1759 Code Common Causes
Front Brake Solenoid Valve Function Malfunction	Faulty front brake solenoid valve
Transmission Control Module (TCM) Disabled	Damaged wiring or connectors
Transmission in Limp Mode	Faulty ATF pressure switch 1
Erratic Shifting Issues	Mechanical failure in the valve body
Loss of Power During Acceleration	Contaminated or low transmission fluid

Symptoms of P1759 Code

The symptoms associated with the P1759 trouble code can vary but generally include:

• Loss of Power: The vehicle may struggle to accelerate, particularly from a stop.
• Erratic or Harsh Shifting: Shifts may feel rough or delayed, indicating transmission issues.
• Limp Mode Activation: The vehicle may enter limp mode, limiting speed and power to protect the transmission from further damage.
• Check Engine Light: The illumination of the check engine light is a common indication that a DTC has been triggered.

Technical Explanation

The P1759 code relates to the front brake solenoid valve’s function within the automatic transmission system. This solenoid is controlled by the Transmission Control Module (TCM), which receives input from various sensors, including:

• Throttle Position Sensor: Monitors the position of the accelerator pedal.
• Vehicle Speed Sensor: Tracks the speed of the vehicle.
• Park/Neutral Position Switch: Ensures that the vehicle is in a proper gear before allowing shifts.

If any of these components fail or if there are issues with the electrical connections, it can lead to improper operation of the solenoid valve, resulting in the P1759 code being set.

Step-by-Step Diagnosis

Diagnosing a P1759 trouble code involves several steps:

1. Retrieve Codes: Use an OBD-II scanner to confirm that P1759 is present and check for any related codes (such as P1757).
2. Visual Inspection: Inspect wiring and connectors associated with the transmission for signs of damage or corrosion.
3. Check Fluid Levels: Ensure that the transmission fluid is at the correct level and not contaminated.
4. Test Components:

• Test the front brake solenoid valve for proper operation.
• Check the ATF pressure switch 1 for functionality.

1. Monitor Live Data: Using a scan tool, monitor live data from relevant sensors while driving to identify any anomalies.

Solution Methods

To resolve issues related to the P1759 code, consider the following methods:

• Repair Damaged Wiring/Connectors: If any wiring or connectors are found to be damaged during inspection, repair or replace them as necessary.
• Replace Front Brake Solenoid Valve: If testing indicates that the solenoid valve is faulty, it should be replaced. This often requires removal of the valve body.
• Replace ATF Pressure Switch 1: If this component is malfunctioning, replacing it may resolve the issue.
• Transmission Fluid Change: If fluid contamination is suspected, perform a complete fluid change and filter replacement.

Cost Estimates

The cost for repairs associated with a P1759 code can vary widely based on labor rates and parts costs:

• Diagnostic Fee: $100 – $150
• Front Brake Solenoid Valve Replacement: $300 – $800 (including parts and labor)
• Wiring Repair/Connector Replacement: $50 – $200 (depending on extent of damage)
• ATF Pressure Switch Replacement: $150 – $300
• Transmission Fluid Change: $100 – $200

Warnings and Recommendations

• Always ensure that you use OEM or high-quality aftermarket parts when replacing components related to your transmission to avoid further issues.
• If you are not comfortable performing these diagnostics or repairs yourself, it is highly recommended to seek professional assistance from an experienced mechanic.
• Regular maintenance of your transmission fluid can prevent many issues related to solenoids and other components.

Closing Paragraph

The P1759 trouble code can present serious challenges for vehicle owners, particularly those driving Nissan or Infiniti models. Understanding its implications and addressing symptoms promptly can prevent further damage to your vehicle’s transmission system. By following proper diagnostic procedures and implementing effective solutions, you can restore your vehicle’s performance and ensure safe operation on the road.

Frequently Asked Questions About P1759

• What does P1759 mean?
  The P1759 code indicates a malfunction with the front brake solenoid valve function in automatic transmissions.
• What are common symptoms of this code?
  Symptoms include loss of power during acceleration, erratic shifting, and activation of limp mode.
• How serious is a P1759 code?
  This code can lead to significant transmission problems if not addressed promptly.
• Can I drive my car with this code?
  It is not advisable as it may cause further damage; driving could exacerbate existing issues.
• What should I do if my check engine light comes on?
  You should retrieve diagnostic codes using an OBD-II scanner immediately.
• How much does it cost to fix a P1759?
  The cost varies but can range from $100 for diagnostics to over $800 for full repairs.
• Is it safe to repair this myself?
  If you have mechanical experience, you can attempt repairs; otherwise, consult a professional.
• What tools do I need for diagnosing this issue?
  An OBD-II scanner and basic hand tools will be necessary for diagnostics and repairs.