Guide To P078B OBD Error Code Solutions

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This is a general type of error code which appears in most of the vehicles with few exceptions. Among the many components shift timing solenoids will allow the automatic transmission to change flawlessly as per the driving needs. The TCM will control and operate the shift solenoids and if it finds the component to be defective, then the P078B code will be stored in your vehicle.

The transmission control module measures the hydraulic pressure with the help of shift solenoids, so that it can apply clutch packs to provide various ratios so that the engine can propel efficiently. The transmission may not shift properly if there is too much fuel. If the TCM finds this defect then it will store the P078B error code in the vehicle.

What causes this problem with the Shift Timing Solenoid A Range/Performance?

• The shift timing solenoid is broken.
• Automatic transmission fluid is bad.
• ATF is less.
• Passage of ATF has obstacles.
• Wiring harness is defective.
• Broken TCM.
• Damaged ECM.
• Problem in connectors or pins as they are broken or eroded.

1. Shift Solenoid - Broken or defective shift solenoids needs immediate replacement so that P078B error code does not appear. 
2. Shift Valves - Looking for the right replacement for your broken shift valves? Get them from Parts Avatar. 
3. Engine Light - Is the engine light broken or damaged? Do you find them defective? Then they must be replaced instantly so as to avoid the P078B error code getting stored in the vehicle
4. Transmission Filter - Check the transmission filter for damages or any debris. If it’s damaged, get the right replacement from Parts Avatar.
5. Transmission Valve Body - Do you find this component to be defective? Are thy broken? Then get them replaced from Parts Avatar. 
6. Connector - Visually inspect the connectors for damages or if they are broken. Replace them as soon as possible. 
7. Powertrain Control Module - P078B is a general type of error code which cause problem in your system. Replace the component as desired.

If you are facing OBD error code P078B, then there are significant common symptoms that can be felt or observed. We have worked out a list here to help you out in understanding this problem better.

Common Symptoms

• Blocked gears.
• Uneven shifts.
• Spin out of transmission.
• Shift timing is not prolific.
• Drivability problems.
• Acceleration is corrupt.
• Overall performance is reduced.

It is very important to fix the fault code P078B. So here are some ways with which you can correct this issue:

• Changing the shift solenoids/ shift valves.
• Cleaning the obstructions in transmission filter.
• Changing the damaged PCM/ connectors.

To do all this, you will need few high-quality auto parts such as shift solenoid, shift valves, engine light, transmission filter, transmission valve body, connector, wiring, PCM and so on. From where will you get them? From your local store? Well, why go there when you can order quality parts with us while sitting in the comfort of your home. So, just browse through our website and order your needed parts today.

If you want to easily diagnose this fault code, then all you have to do is to follow the steps which are mentioned below:

• Firstly, you have to check if the automatic transmission fluid smells good, or if they are dirty and have different colors. This can be one of the problems if you don’t remember when you lastly changed the fluid or you may have avoided a simple maintenance service which causes this error code in your vehicle. Clear the blocks and replace with clean fluid.
• You can access the shift solenoids externally, depending on your model if the error code still pops up. Check the wires and connectors of the component for damage and fix them if there are any issues. Do you find any leaks? Then clean them.
• Try testing the shift solenoid through many ways. One of the tests may include using a multimeter to check the electrical integrity by measuring the resistance between different pins in the solenoid which is called resistance test. You can test the mechanical operation by applying voltage manually to the solenoids. You can find this information in the service manual of your vehicle.
• Test the TCM circuit for the proper functioning of the circuit and sensor. Perform the same test as performed above but by connecting the pins to TCM/ECM. This can help you to check the electrical integrity of the solenoid and the circuit as well.

Common Mistakes When Diagnosing the P078B

• Defective transmission control module.
• Low fluid in transmission.
• Transmission shift solenoid is faulty.
• Defective transmission valve body.
• Issue with cables.