Error Code P0781: What It Means & What To Do?

<<See All OBD Codes

The trouble code P0781 can be explicated as 1-2 Shift Malfunction. If the powertrain control module will store the P0781 fault code, then it would mean that the PCM has detected some issue in the 1-2 shift function.

The brighter you are, the more you have to learn! That’s why we are here to provide you more knowledge about the P0781 trouble code. This diagnostic fault code is a generic powertrain code, which means that it would apply to the OBD-II equipped vehicles. The specific repair steps can vary as it depends upon the vehicle make and model. One thing which you must keep in mind that its symptoms as well as causes would surely vary as it depends upon a number of things

What causes this problem with the 1-2 Shift Malfunction?

• Faulty 1-2 shift solenoid
• Issue of electrical short to power
• There can be an electrical short to ground
• The power or ground circuit wiring might be opened or disconnected
• Internal failure in the TCM or PCM

1. Powertrain Control Module - PCM is perfectly fine but still but having that trouble code P0781 flashing? In such a situation your Powertrain Control Module might be faulty. Why don’t you think of getting that replaced?
2. Speed Sensor - The P0781 code can also arise due to some issues in Speed Sensor. So, it is advised to replace them as soon as possible.
3. Automatic Transmission Sensor- P0781 code does not really end up spoiling your Speed Sensor, but it might also accompany few automatic transmission sensor issues. We have best automatic transmission sensor with us.
4. Body Control Module Component - Are you facing OBD Error Code P0781? Don’t worry as you can fix this issue with new Body Control Module Component. We care for our customers, that’s why we have Body Control Module Component for every make and model.
5. Automatic Transmission Fluid - Faults in the Automatic Transmission Fluid can cause a lot of issues. It would be nice if you get it replaced on time.

It is essential to know the symptoms of an issue as only then you would be able to solve the problem. So that’s why we have listed out some major symptoms of OBD Code P0781 here:

Common Symptoms

• Car dies while stopped
• Car idles irregularly
• Car may pause while accelerating
• Absence of power while driving
• Check engine light can start appearing
• The vehicle might take longer to start up, or does not start up at all
• Rise in overall fuel consumption

If you wish to correct this fault code, then you have to follow certain steps. Correcting a problem needs your careful attention. Here are some ways with the help of which you will be able to correct the OBD Code P0781:

• Rehabilitate the defaults in the automatic transmission filter
• You must fix the topping off the transmission fluid
• Make sure to mend the faulty shift solenoids
• It is essential to restore the flawed transmission fluid
• Repair or replace the quirky wiring
• The malfunctioning connections should be repaired or cleaned as per the need

Parts Avatar Canada is here to solve all your issues related to car parts. We have stocked a wide range of best priced transmission rebuild, transmission oil, transmission sensor, pressure control solenoid and a lot more to help you out in fixing your car.

If you want to easily diagnose this trouble code, then you must follow the steps which are mentioned here as below:

Do you want to diagnose the P0781 error code successfully? Then you will need a scanner and a digital volt/ohmmeter. Generally, every vehicle with an automatic transmission produced since the mid-eighties is equipped with some type of computer controlled automatic transmission system. A sophisticated computerized control system is utilized by the OBD-II equipped vehicles that calculates a number of engine drivability inputs with vehicle speed inputs, engine/turbine speed inputs, and transmission output speed inputs to determine the desired gear ratio necessary to achieve maximum fuel efficiency, to optimize engine performance, and provide the greatest engine and transmission longevity. The input data is calculated by the powertrain control module and initiates upshifting and downshifting by using strategically designed shift solenoids to actuate fluid transfer between the hydraulic circuits of each set of corresponding gears. If there are a lot of stored shift solenoid codes then it would indicate that a transmission component slipping or delayed engagement condition has occurred. The automatic transmission uses a high-pressure pump to circulate fluid through the transmission hydraulic circuits in the transmission housing and valve body. Now if the transmission pressure is not sufficient enough to actuate gear changes, this type of code might exist. Insufficient fluid pressure is most often caused due to less or grubby transmission fluid condition.

You must begin the transmission diagnosis with an inspection of the transmission fluid dipstick. Just make sure that the fluid level should be within manufacturer’s specified recommendations and that the fluid is in nice condition. Fluid that smells burned or unusual in any way should be considered inappropriate. If the fluid is burned, then it would indicate that the transmission has been operated during a low fluid level condition and may have experienced catastrophic internal mechanical failure. If the fluid smells or appears burned, then the transmission pan should be removed and inspect for the presence of clutch material and other debris. If such contaminants are present in the transmission pan, a total rebuild, fluid flush and replacement, and a new torque converter would be needed before the transmission will function correctly. If no debris is found in the transmission pan, then you should check all internal wiring and connectors. Search for shorted or burned wiring and replace circuitry and connectors as required. Most applications will require replacement of the full internal transmission harness if discrepancies are noted. If the system wiring, connectors, and components appear to be in normal working order, connect the scanner to the diagnostic connector and record all stored trouble codes and freeze frame data. The intermittent conditions can be diagnosed easily with the help of this information that may have contributed to this code being stored. Now once the codes have been cleared, operate the vehicle to see if the code returns. If the code fails to immediately return, then there is a situation of intermittent condition

Intermittent conditions can prove to be challenging to diagnose and in extreme cases may have to be allowed to worsen before a correct diagnosis can be made. Now if the transmission fluid is in decent shape, but the overall level of the fluid is less, then you should add enough fluid to locate a leak and repair it. Fill the transmission with fluid, allow the vehicle to reach normal operating temperature, and test drive it to see if the transmission operates normally and to determine whether the code will return. If the transmission operates normally and the code doesn’t return, then it was likely caused by transmission slippage due to a low fluid level/pressure condition. If the code is returning back again and the transmission slips or suffers from delayed engagement, check pump pressure using a manual pressure gauge. Obtain a hydraulic pressure diagram pertaining to the vehicle and thread the end of the gauge into the appropriate opening on the transmission housing to record pump pressure. Your findings should be compared with manufacturer’s specifications and make repairs as per the requirements. Typical causes of low pump pressure include clogged hydraulic passages, a defective pump, faulty shift solenoids, or a faulty electronic pressure regulator. There would be a need of transmission removal in the pump replacement and partial disassembly. If the code immediately returns, and the transmission seems to operate normally, then inspect for reference voltage and ground signals at the affected shift solenoid. If either the reference voltage or ground circuits are open, then a digital volt/ohmmeter should be used to check for continuity as well as resistance in all circuits.

Repair or replace system circuits/connectors as required and retest the system to ensure that repairs were successful. Using the manufacturer’s wiring diagram for the affected shift solenoid, test all related circuits and the solenoid itself for resistance and continuity and compare your findings with manufacturer’s specifications. Repair or replace system circuitry, connectors, and/or components that fail to coincide with manufacturer’s specs. Always retest the system to ensure a successful repair. If all system circuits are intact connecting the scanner to the diagnostic connector and attempt to manually activate the shift solenoid/s. If the shift solenoid functions properly and all circuits coincide with manufacturer’s specifications, suspect a defective PCM. Just keep in mind that PCM failure is rare and it will require reprogramming during replacement. If the shift solenoid fails to activate manually, replace the solenoid (or solenoid pack) and retest the transmission control system.

Common Mistakes When Diagnosing The P0781 Code

• Non-performance of the transmission control module
• Failure in the TCM
• Level of the Transmission fluid level might start failing
• Non-observance of the Transmission shift solenoid
• There can be some faults in the wiring