P0843 OBD Error Code: Problem & Solutions

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Is your vehicle flashing that OBD error code P0843? Is your faulty TCM forcing you to undergo a complete vehicle check-up? Well, in this case we recommend you to undergo a complete diagnosis of this problem and maybe replace your faulty transmission fluid pressure sensor circuit “A” and other related parts.

In order to solve any problem, you need to understand that problem completely, so let's get started with this problem from the very start i.e. what exactly this OBD error code P0843 indicates.

Your vehicle’s TCM, also known as the powertrain control module will set up this error code P0843 when it detects voltage problems with the transmission fluid pressure sensor. Error code P0843 also indicates that there exists higher than manufacturer’s specified voltage in the transmission fluid pressure sensor/switch “A” circuit. Wondering what causes this problem? If yes, then take a look at the section below.

What causes this problem with the Transmission Fluid Pressure Sensor/Switch "A" Circuit High?

• Faulty transmission fluid pressure sensor harnesses or connectors
• Possibly failing Powertrain Control Module
• Bad TFPS circuit
• Extremely low transmission fluid level
• Poor or dirty transmission fluid
• Very low transmission fluid level
• Possible blockages in the internal/external transmission lines
• Programming errors with the powertrain control module
• Malfunctioning transmission fluid pressure sensor/switch “A”
• Possible open in the TFPS sensor circuit
• TFPS sensor having a short or voltage
• Failing TFPS sensor
• Internal mechanical issues with the transmission
• Open or shorted transmission fluid pressure sensor circuit “A”

1. Transmission Control Module - Replacing the faulty TCM becomes really important to get rid of this problem. What are you waiting for? Just browse through our website to find best transmission control modules for your vehicles.
2. Digital Voltmeter - We are here to help you out in becoming that DIY guy you always wished to be with our extensive collection of Diagnostic tools including digital voltmeters. So, what are you waiting for? Just find your desired parts and tools with us.
3. Powertrain Control Module - We have in stock wide selection of PCM specific to every make and model. You can shop them with us 24x7 in just one click.
4. Transmission Fluid Pressure Sensor - If you want or are looking for transmission fluid pressure sensor to fix your vehicle, we have a good news for you. We have in stock transmission fluid pressure sensor for you and that too at the best prices ever online.
5. Automatic Transmission Module - To solve this issue you might also need to undergo automatic transmission module replacement. You can easily shop them with us.
6. Engine Control Module - If your vehicle’s engine control module is defective it can cause this issue, so you might also need to replace the car’s ECM to correct this engine error code P0843.
7. Transmission Shift Solenoid - We are sure that for fixing this problem you will need to replace the transmission shift solenoid. With us you can also find a wide variety of transmission shift solenoid from top auto brands to fix this OBD Error code P0843.
8. Hydraulic Clutch - Need hydraulic clutches and parts? Well, now is the time you get one for your car with us at PartsAvatar.

it is vital to know the symptoms of an issue as only then you will be able to solve the problem. so that’s why we have listed out some major symptoms of obd code P0843 here:

Common Symptoms

• Service engine soon warning light flashing
• Malfunction indicator light will turn on
• There will be a change in transmission shift quality
• Rise in fuel consumption
• Delayed or incorrect transmission shifting
• Limp mode set in 2nd or 3rd gear

Have a look at some ways with which you can correct the P0843 code:

• Inspect, repair or replacing the transmission fluid pressure sensor, if found faulty
• Repair or replace the transmission fluid pressure control solenoid, if found faulty
• Flush the transmission fluid and refill it with a new and right one
• Repair or replace the damaged or blocked fluid hoses

Parts Avatar Canada is here to solve all your issues related to car parts. We have stocked a wide range of best priced transmission fluid pressure sensor, engine control module, PCM, Transmission Fluid Pressure Switch, Transmission Control Module, TCM, hydraulic clutch, transmission fluid pressure control solenoid and a lot 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 P0843 code to be stored:

Use the technical service bulletins specific to your vehicle’s make and model to help you understand the problem properly. This will not only help you to understand the specific issue but also help you to understand steps on how to fix it. Believe us it will save you a lot of time and money while diagnosing not only this code but for any other code too. Also, you should start your diagnosis with all the power related error code or with the multiple code diagnosis as it will help you in understanding the reasons behind the error code P0843. Next on your list to do is to locate transmission fluid pressure sensor/switch on your vehicle to begin with the specific diagnosis. It will likely be attached to your vehicle’s valve body side inside the transmission. Once you figure out its location, next step for you to do is to check the connectors and wirings for any loose ends, bare wires, rubbing, scraping, burn spots or melted plastics. Now, take the connector apart and inspect the terminals very carefully inside the connector. Make sure that they don’t look burnt or have a green tint indicating corrosion. Make use of an electrical contact cleaner and a plastic bristle brush if cleaning of the terminals needs to be cleaned. Let dry and apply electrical grease where the terminals contact. Next step is to use a scan tool and clear all the existing trouble code from memory, and check if the P0843 code returns. In case it does not then the problem was mainly with the connectors only. In case it does return then the connections were most likely your problem. This is a common area of concern for this code, as the external transmission connections have the greatest number of issues with corrosion. In case the code returns, then you will need to inspect the TFPS sensor and all the related connectors and circuits. Turn off the key and disconnect the electrical connectors at the TFPS sensor. Now, connect the digital voltmeter either to the ground or to the low reference terminal at the TFPS sensor wiring harness connector. Also connect the red lead of the DVOM to the signal terminals at the TFPS sensor wiring harness connector. Now, turn on the key and check for the manufacturer’s specifications. Make sure that the voltmeter reads either 12 volts or 5 volts. Wiggle the connections to check if they change. In case the voltage is incorrect, repair the power or ground wire, or replace the PCM/TCM. Now, if this test is passed then connect one lead of an ohmmeter to the signal terminal at the TFPS sensor and the other lead to the ground or low reference terminal at the sensor. Next, check for the manufacturer’s specifications on the resistance of the sensor to accurately test the resistance to pressure when there is no pressure applied to it. Again, wiggle the connector at the Transmission Fluid Pressure Sensor/Switch while monitoring the resistance. If the ohmmeter readings do not pass, replace the TFPS. If you still continue to get the P0843 error code in spite of passing all these prior tests then it is signalling a failed TFPS sensor, although a failed PCM/TCM could not be ruled out, nor could internal transmission malfunctions until the TFPS sensor had been replaced. If you are in doubt, we suggest you to seek help from a trained automotive diagnostician. PCM/TCMs must be programmed or calibrated to the vehicle in order to be installed correctly.

Common Mistakes When Diagnosing the P0843 Code

Few of the common mistakes that you can commit while diagnosing this P0843 generic obd codes are listed as follows:

• Failing Transmission Control Module (TCM)
• Pretty low Transmission fluid level
• Failing Transmission fluid pressure sensor
• Wiring issue