Error Code P0749: What It Means & What To Do?

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The OBD error code P0749 is caused due to a voltage issue with the transmission fluid pressure control solenoid, and its signal sent to the engine computer. The purpose of the solenoid is to help control the fuel pressure of the transmission. An issue here may result in inappropriate pressure for shifting being produced.

In your vehicle there is a pressure control solenoid, which is basically an electronic pressure regulator. Its job is to control the transmission line pressure as per the current flow. It does this through its coil windings, as there is an increase in current flow the magnetic field produced by these coils moves the solenoids plunger further away from the exhaust port. When the exhaust port opens, the output fluid pressure regulated by the PC solenoid valve decreased, which in turn decreases the line pressure too. In order to suit the driving condition responding to the signal sent from the TCM, the line pressure solenoid valve regulates the oil pump discharge.

What causes this problem with the Pressure Control Solenoid A Intermittent?

• Defect in the Pressure Control Solenoid
• Dirty or contaminated transmission oil
• The transmission filter has become clogged or dirty.
• Defectiveness in the Transmission Pump
• Defectiveness Transmission Valve Body
• Restrictions in the hydraulic passages
• Corrosion or damage of the connector
• Fault or damage of the wiring
• PCM Failure

1. Pressure Control Solenoid - Depending on the extent of damage, you can try to repair or replace it to get rid of the P0749 code.
2. Transmission Filter - Only go for branded car parts, we have a huge variety available for you. Just visit our website and browse through, order easily and have the products shipped to you within days.
3. Transmission Pump - Repair and replace the pump as needed.
4. Transmission Valve - Quality OEM parts available on our website. You can order 24x7 and have it delivered to your doorstep. We ship to the remotest areas across Canada.
5. Pressure Control Solenoid Connector - Repair and replace the connector as per need. This should resolve your P0749 OBD error.
6. Hydraulic Pipes - Try to repair if you decide to replace, opt only go for the best quality for long term solution.
7. Powertrain Control Module - Replace your PCM with us, we offer free shipping on orders over CAD $99.

We at Parts Avatar Canada care for our customers, and that’s why we will help you to diagnose P0749 code by listing out some major symptoms. They are mentioned below as follows:

Common Symptoms

• Check Engine Light is on
• Vehicle doesn’t shift from gear to gear as it used to
• Vehicle may no longer be driveable
• Low fuel economy
• There are no adverse conditions noticed by the driver in some rare cases
• Performance problems may be see in some cases

Learn the ways with which you can correct this trouble code:

• Replacing transmission fluid pressure control solenoid
• Replacing as well as flushing the transmission fluid
• Fluid hoses to be repaired if damaged or blocked 

However, if you face any issue then we have stocked a wide range of best priced Pressure Control Solenoid, Transmission Filter, Transmission Pump, Transmission Valve, Pressure Control Solenoid Connector, Hydraulic Pipes, Powertrain Control Module and more to help you out in fixing your car.

It is essential to diagnose this fault code. Here are some steps which a mechanic should follow for diagnosing the problem that triggered a P0749 code to be stored:

• Inspect the transmission fluid dipstick. Check and make sure the transmission fluid is not contaminated or possessing any burned smell. If that is the case you will have to deem the fluid as inadequate and replace it. The level of the fluid should also be as per manufacturer's specifications for your particular vehicle.
• Burned fluid is very much an indication that the transmission was working when the fluid was well below the required level. This also means that it has suffered terrible internal mechanical failure due to this. If the fluid is burned, you have to remove the transmission pan and check for any clutch material or debris present.
• Inspect for any shorted or burned wiring and accordingly replace the circuitry and the connectors. If they appear normal upon inspection, then you can connect the scanner to your vehicle's diagnostic port and retrieve all stored codes and freeze frame the data. Make note of the codes to for reference if there’s an intermittent code. Then clear all the data and go for a test drive.
• If the PCM enters readiness mode (code doesn’t set immediately), it would mean you have an intermittent condition. The condition may have to worsen before correct diagnosis can be drawn in such a situation, as intermittent conditions as far more difficult to understand and resolve.
• If the code immediately reset, and the transmission is working fine, then you will have to check reference voltage and ground signals at the electronic pressure control solenoid.
• Collect your findings and compare them with the manufacturer's requirements. All the discrepancies will have to be accordingly corrected. The usual culprits of a low-pressure pump are clogged hydraulic passages, a defective pump, faulty shift solenoids, or a faulty electronic pressure regulator. In order to replace the pump, you will have to remove the transmission and perform partial disassembly.
• All damaged system circuitry and connectors will have to accordingly be repaired or replaced. To find the exact location of the pressure control solenoid, use your vehicle manufacturers wiring diagrams, test all the related circuitry as well as the solenoid. Remember to check both resistance as well as continuity, and again compare your findings to the specifics of your vehicle manufacturer.
• You should always restart the system, to confirm success in repairs. If you have found that all the system circuitry is working fine and is in good condition, then connect the scanner to the diagnostic connector and try to manually activate the electronic pressure control solenoid. If it’s working fine, then suspect a defect in the high-pressure pump or torque converter, In very rare cases the issue could also be with the Powertrain Control Module. If however the electronic pressure control solenoid fails to activate during manual check, you will have to replace the solenoid and retest the transmission control system.

Common Mistakes When Diagnosing the P0749 Code

• Not considering the dirty or low fluid as the problem maker
• Overlooking the possibility of internal damage