What the P0745 code means
When the code P0745 appears in your powertrain control module (PCM), it means that the PCM is not reading the correct electrical voltage drops from the Pressure Control Solenoid as it does its job. It may also be that your PCM reads the correct electrical readings but that the performance of the Pressure Control Solenoid is incorrect.
What causes the P0745 code?
The most common causes for a P0745 code include a defective valve body or pressure solenoid. Your vehicle may also suffer from poor or defective wiring on your pressure solenoid. Another cause could be a dirty transmission that inhibits and restricts your vehicle’s hydraulic passages.
What are the symptoms of the P0745 code?
Some symptoms associated with this code may include an illuminated Check Engine light, or more severe symptoms such as a vehicle that cannot be driven, a decrease in your vehicle’s fuel economy, and an inability to shift from one gear to another.
How does a mechanic diagnose the P0745 code?
When diagnosing a P0745 code, you should always record the freeze frame data and then simulate these code-setting conditions with a test drive at your vehicle’s freeze frame road speed. Start from a stopped position and accelerate slowly. Pay attention to the scan data and check if your PCM is commanding the Pressure Control Solenoid. If the PCM is commanding the Pressure Control Solenoid with a higher duty cycle and the transmission is not performing as it should, then you may have discovered the issue. Your next step is to begin doing what are called “pinpoint tests,” which in this case are continuity tests and voltage drops for the Pressure Control Solenoid. If the electrical tests are within the recommended parameters, then using a pressure gauge you should test the performance of the Pressure Control Solenoid. Remember to always examine the condition of the fluid. It should be a clear red color, almost like a watered-down cranberry juice. If it appears burned or brown or dirty, then you will need to change your fluid immediately.
Common mistakes when diagnosing the P0745 code
Some technicians will mistake a P0745 for a misfiring engine or a problem with your vehicle’s performance. Others have assumed that your vehicle is suffering from a driveline problem, when in fact the issue had to do with a defective valve body or solenoid.
How serious is a P0745
In many cases, a P0745 is very serious, particularly when your vehicle will not start or your vehicle will not shift into gear properly. Typically, a professional technician should handle a P3068 code, especially considering that you will need costly diagnostic equipment and extensive knowledge to handle the repairs yourself.
What repairs can fix the P0745 code?
If your vehicle’s fluid smells or appears burned or scorched, you will need to remove the transmission pan and look for for the presence of clutch material and other dirt and debris. If you do find contaminants in the transmission pan, you may need to do a complete rebuild along with a fluid flush and fluid replacement. In some cases, a new torque converter may need to be installed before your transmission can begin to function properly again. If you do not see any debris in your transmission pan, you should visually inspect all internal wiring and connectors and replace or repair any shorted, damaged, or corroded wires and connectors.
Additional comments for consideration regarding the P0745 code
In some cases, a P0745 will prevent your car from starting or shifting smoothly from one gear to another. Another, possibly more serious issue, is the emission of toxic gases from your vehicle. You may notice unburned droplets of raw fuel that affect your breathing. Your vehicle may also emit higher levels of carbon monoxide and nitrous oxide, which both contribute to smog. Therefore, this issue is something that you will want to fix right away. But please beware that fixing this issue can become very complex and that doing the repairs on your own may involve long hours of labor with expensive diagnostic equipment. Therefore, it is important to do the correct amount of research before you begin to work. Do not hesitate to contact a professional technician for advice about this issue.
Need help with a P0745 code?
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