P0959 - Automatic Manual Shift Circuit Intermittent

P0959 – OBD-II Trouble Code Technical Description

Intermittent circuit of automatic switching to manual mode 

What does the fault code mean P0959?

Trouble code P0959 indicates problems with the automatic shift circuit in manual mode. This code refers to the vehicle's OBD-II (On-Board Diagnostics II) system and is used to identify faults in the engine and transmission control system.

More specifically, P0959 means that an intermittent signal is detected in the circuit responsible for automatic transmission shifting in manual mode. This error can affect the normal functioning of the transmission control system and lead to problems when manually shifting gears.

Possible reasons

Trouble code P0959 indicates problems with the automatic shift circuit in manual mode. Here are some possible reasons that could cause this condition:

1. Malfunction in the shift solenoid (SSS): The solenoids control gear shifting, and problems with them can result in a P0959 code.
2. Damage to wiring or connectors: Opens, shorts, or damaged wiring, as well as poor connections in connectors, can cause circuit problems.
3. Malfunction in the transmission control unit: If the transmission control module is experiencing problems, it can cause errors in the signals and cause a trouble code to appear.
4. Problems with the gear shift mechanism: The gear shift mechanism, such as the steering wheel shifter, may be faulty and cause the error.
5. Problems with sensors: The sensors responsible for monitoring the condition of the transmission may be damaged or produce incorrect signals.
6. Problems with actuators: Actuators that control shift mechanisms can also cause problems.
7. Problems with transmission control software: Incorrect operation of the software that controls the transmission can cause errors and trouble codes.

To accurately determine the cause of the P0959 code, it is recommended to conduct more detailed diagnostics using specialized equipment and, possibly, contact a professional auto repair shop.

What are the symptoms of a fault code? P0959?

Trouble code P0959 indicates problems with the automatic shift circuit in manual mode. Symptoms associated with this code can vary depending on the specific problem, but they typically include the following:

1. Malfunction in manual gear shift mode: There may be difficulties when manually changing gears, deviations from the expected behavior when using manual mode.
2. Manual mode not working: In some cases, the vehicle may refuse to enter manual gear shift mode, which may limit the driver's options.
3. Changes in transmission operation: Incorrect or jerky gear shifts may occur in automatic transmission mode.
4. Check Engine Light Appears: Typically, when the P0959 trouble code occurs, the Check Engine light on the dashboard will illuminate, indicating that there is a problem that needs to be addressed.
5. Reduced performance and fuel economy: Improper transmission operation can result in poor vehicle performance and poor fuel economy.

If these symptoms occur, it is recommended that you contact a qualified auto mechanic or service center to diagnose and repair the problem.

How to diagnose a fault code P0959?

To diagnose DTC P0959, it is recommended that you follow a specific sequence of steps:

1. Scanning error codes: Use an OBD-II diagnostic scanner to read error codes. This will allow you to confirm the presence of the P0959 code and identify other related codes if present.
2. Checking wiring and connectors: Visually inspect the wiring, looking for damage, breaks, shorts, and poor connections in the area associated with the automatic shift circuit. You may need to use a multimeter to check the resistance and continuity of the wires.
3. Solenoid Check: Check the condition of the solenoids responsible for automatic gear shifting in manual mode. This may require removing the transmission cover. Solenoids can be tested for resistance and their electrical operation.
4. Diagnostics of the transmission control unit: Use a diagnostic scanner to read additional information provided by the transmission control module. This could include live data that can help identify problems.
5. Checking the gear shift mechanism: Check that the gear shift mechanism, such as the steering wheel switch, is operating correctly. Make sure there are no mechanical problems preventing proper shifting.
6. Sensor check: Check the status of sensors related to transmission monitoring. These could be switch position sensors, speed sensors, etc.
7. Software update: Check to see if there are any available updates for the transmission control module software. In some cases, updating the software may resolve problems.
8. Professional diagnostics: If you are not confident in your skills or do not have the necessary equipment, it is recommended that you contact a professional auto mechanic or auto repair shop for a more detailed diagnosis and solution to the problem.

Diagnostic errors

When diagnosing car problems, including trouble codes, common errors can occur. Some of them include:

1. Insufficient diagnosis details: Limiting the diagnosis to the error code alone without additional testing may result in an incorrect determination of the cause.
2. Ignoring other error codes: A vehicle may have multiple error codes, and focusing on just one may result in missing important information.
3. Replacement of parts without prior inspection: Replacing components without sufficient diagnostics can lead to unnecessary costs and not solve the underlying problem.
4. Incorrect interpretation of data: Incorrect interpretation of the data provided by the diagnostic scanner can lead to erroneous conclusions about the state of the system.
5. Neglect of visual inspection: Some problems can be identified visually, such as damaged wiring, cracks, corrosion or leaks. Neglecting this aspect may result in missing important details.
6. Unaccounted external factors: Environmental factors, such as vehicle damage from an accident or electrical problems, can cause problems other than the transmission.
7. Use of low quality spare parts: Replacing low quality parts can create new problems and lead to unstable system operation.
8. Insufficient expertise: Incorrect interpretation of data and lack of expertise in vehicle technology can lead to diagnostic errors.
9. Lack of software updates: Failure to use the latest software updates for diagnostic devices may reduce diagnostic performance.

For a successful diagnosis, it is important to use a systematic and appropriate method, taking into account all aspects of the problem and paying attention to various factors. If you are unsure, it is recommended to contact a professional.

How serious is the fault code? P0959?

Trouble code P0959 indicates problems with the automatic shift circuit in manual mode. The severity of this problem may vary depending on the specific circumstances, transmission type, and other factors. Here are a few aspects to consider:

1. Performance Impact: Automatic transmission problems can affect the overall performance of the vehicle. This can affect ride quality, fuel consumption, and even the ability to manually shift gears correctly.
2. Functionality limitation: If manual shift mode is inoperative due to P0959, it may limit the driver's ability to control the transmission.
3. Risk of transmission damage: Incorrect or lack of gear shifting can place additional stress on the transmission, which can lead to wear and damage in the long run.
4. Potential security issues: In some situations, failure of the gearshift system may cause problems with vehicle control, which may affect driving safety.

With these aspects in mind, the P0959 code should be considered serious and it is recommended that steps be taken to resolve the problem. Faults in the transmission system can lead to additional problems if they are not corrected in a timely manner. It is important to have your vehicle diagnosed and repaired as soon as possible to maintain proper transmission performance and ensure safe driving.

What repair will help eliminate the code? P0959?

Resolving trouble code P0959 will require detailed diagnostics to determine the specific cause of the problem. Depending on the identified malfunction, the following types of repairs may be required:

1. Shift Solenoid (SSS) Replacement or Repair: If the manual shift solenoid is faulty, it may need to be replaced or repaired.
2. Checking and restoring wiring: Inspect the wiring, connections and connectors associated with the automatic shift circuit. If damaged wiring or poor connections are found, they should be repaired or replaced.
3. Diagnostics of the transmission control unit: Perform a thorough diagnosis of the transmission control module to identify possible problems with software or electronic components. In some cases, it may be necessary to restore or replace the control unit.
4. Checking and updating software: Check to see if there are any software updates available for the transmission control unit. Updating the software may resolve compatibility issues or fix bugs.
5. Checking the gear shift mechanism: Check the condition of the gear shift mechanism, such as the steering wheel switch. If mechanical problems are discovered, they may require repair or replacement.
6. Checking and replacing sensors: Check sensors related to transmission health monitoring. Damaged or faulty sensors can be replaced.

It is important to note that to successfully resolve the P0959 code, it is better to contact an experienced auto mechanic or auto repair shop. Diagnosing electronic systems and transmission components requires specialized knowledge and equipment.

What is P0959 Engine Code [Quick Guide]

P0959 – Brand-specific information

1. Chevrolet/GM:
   • P0959: Shift Solenoid “S” Circuit Intermittent
2. Ford:
   • P0959: Auto Shift Manual Mode Circuit Low
3. Toyota:
   • P0959: Auto Shift Manual Mode Circuit Range / Performance
4. Sling:
   • P0959: Auto Shift Manual Mode Circuit Range / Performance
5. Volkswagen (VW):
   • P0959: Auto Shift Manual Mode Circuit Range / Performance
6. BMW:
   • P0959: Auto Shift Manual Mode Circuit Range / Performance
7. Mercedes Benz:
   • P0959: Auto Shift Manual Mode Circuit Range / Performance
8. Nissan:
   • P0959: Auto Shift Manual Mode Circuit Range / Performance