What is the P0759 fault number? What is the description of the Shift Solenoid “B” Intermittent? How do I fix the P0759 fault code What are the causes and symptoms of P0759 error code?
What is the P0759 Fault code? What does it all mean?
The code P0759 is activated when the powertrain controller module (PCM), detects an intermittent signal at the “B” shift solenoid. This code could be accompanied by other shift codes.
Computer-controlled automatic transmissions use shift solenoids in order to adjust gear ratios. There are three solenoids in automatic transmissions. They are called A, C, and P0756.
Shift solenoids, managed by the PCM or transmission control module (TCM), are used to adjust the transmission gear ratio. This is done by directing the transmission fluid to various hydraulic circuits. The solenoid controlling the transmission directs pressurized liquid to the appropriate hydraulic circuit depending on the vehicle’s speed. The hydraulic circuit maintains proper alignment of all transmission components by applying pressure. You can maximize engine performance by using different gear combinations.
If the PCM or TCM detects an intermittent/intermittent voltage signal at the “B” shift solenoid, a code P0759 is set. The main problem is not an electrical one, but a mechanical failure. This is most often caused by debris blocking hydraulic fluid flow. This code will cause the check engine light to go on in the instrument cluster. A transmission warning light or overdrive may also be on.
P0759 fault codes can be found on many vehicles, including, but not limited, to Ford, Duramax and Mercedes-Benz models.
What are the possible causes of the P0759 Fault code?
Here are some reasons why P0759 should be set.
- – Connectors and/or wiring that are damaged, burnedt, shorted/disconnected, or corroded
- – Defective “B” shift solenoid
- – Oil with low or no transmission
- Use of incompatible or unsuitable transmission fluid
- – Clogged or dirty transmission filter
- – Clogged hydraulic fluid passage channel
- – Hydraulic control unit for transmission failure
- – A clogged or defective transmission pump
- – Other mechanical problems in the gearbox
- Software update required for a defective PCM (or transmission control module) or deficient PCM.
What are the P0759 Malfunction Code Symptoms
You may experience the following symptoms if your vehicle has the code P0759:
- – Illumination for the check engine light
- Transmission warning light turns on
- – Gearbox slip
- Gearbox stuck in any gear (especially 2-3).
- – Incorrect or delayed gear changes
- Engine stalling occurs when the vehicle is close to stopping
- – While in gear, the vehicle doesn’t move.
- – Increased fuel consumption
- – The gearbox is overheated
- – The engine might experience misfire-like symptoms in some cases.
- – The PCM can be set to failsafe mode
How to Fix the P0759 Fault Code
It is a common error to replace the shift solenoid when trying to repair this code. A mechanic should first examine the condition of the transmission fluid when diagnosing solenoid-related fault codes. Transmission fluid that is corroded or soiled may cause internal damage. The transmission fluid should be clean and free from leaks. If there are signs of corrosion or damage to the connectors and harness, they should be inspected carefully. If there are no problems, the 2-shift solenoids should still be tested according to the manufacturer’s recommendations. Other components, such as the hydraulic control unit or pressure regulating valve, may also be defective if the solenoid works properly.
Some of the possible repairs that can resolve the P0759 fault codes are:
- Ensure that all codes are cleared before you drive the car to test if they return.
- – Clean the transmission and fill the transmission with fluid.
- – Replacing transmission filter
- – Repair of damaged wires and connectors, as well as open or short circuits to the solenoid
- – Cleaning corrosion from connectors
- – Replacing the defective solenoid for “B” shift
- – Replacing a defective hydraulic control unit
- – Pump replacement or removal of blockages
- – Reprogramming the TCM/PCM
How Serious Is the P0759 Fault Coding?
This code is usually mild to moderately severe. However, if it is not addressed promptly, it can become more severe. It can cause serious problems to the vehicle’s driving ability. You may notice that the transmission can heat up, which could lead to problems in shifting gears or even not changing them at all. The PCM can enter fail-safe mode and limit the engine speed, making it very difficult to drive. It is important to repair the fault as soon possible, as this will lead to high repair costs.
