P0845 - OBD Trouble Code

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OBD error code P0845 is a generic error code. Now you must be wondering what does this term generic code means. Generic codes are the code that apply to all makes and models.

So, what is this OBD error code P0845 about? This error code indicates that there is some issue with your transmission fluid pressure sensor/switch circuit “B”. If you wish to know more about this error code you will need to go through the subsequent sections.

If your vehicle’s powertrain control module detects unusual voltage readings coming from the fluid pressure sensor circuit, it will set this error code P0845. In case the fluid pressure sensor lacks the right amount of fluid pressure, then it cannot achieve the right amount of transmission pressure and this will lead the PCM to set the error code P0845. To know more about this error code, take a look at few of its common causes below.

What causes this problem with the Transmission Fluid Pressure Sensor/Switch "B" Circuit

• Transmission fluid passages if blocked
• Failing internal transmission
• Low levels of transmission fluid
• Bad, wrong, dirty or contaminated transmission fluid
• Malfunctioning powertrain control module or transmission control module

1. Transmission Control Module - Need to undergo transmission control module replacement? If Yes, then you have arrived at the right place. We have in stock for you high end TCM’s from top brands.
2. Digital Voltmeter - If you are looking for digital voltmeters online, then you can simply visit our website and get your parts for all makes and models.
3. Powertrain Control Module - Chances are that your PCM, itself is damaged and is demanding for a quick change.
4. Transmission Fluid Pressure Sensor - P0845 error code might have to do with transmission fluid pressure sensor faulty. The PartsAvatar website offers a comprehensive range of transmission parts for you to select from that is the right fit for your car.
5. Automatic Transmission Module - Well, if you really wish to get rid of this problem you might need to undergo automatic transmission replacements. You can easily find them with us.
6. Engine Control Module - if you need engine control module to correct your obd error code P0845 then you can simply browse through our PartsAvatar Canada website and get your hands on the best selection parts available.

If you are facing OBD error code P0845, 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

• Hard transmission shifting
• Transmission slipping
• Transmission overheating
• Fall in fuel efficiency
• Failing torque converter clutch engagement
• Illumination of check engine light

It is very important to fix the fault code P0845. So here are some ways with which you can correct this issue:

• First step is to replace the damaged wiring, connectors, or components.
• Next thing is to undergo transmission rebuilt if found damaged due to a low fluid condition.
• After that install a new torque converter while rebuilding the transmission.
• Next, fix the internal transmission issues.
• Clean the blocked transmission fluid passages.
• If the torque converter is found to be faulty make sure to replace it.
• Also, replace the transmission fluid pressure sensor, electronic pressure regulator and electronic pressure control solenoid, if faulty.
• Flush out the dirty transmission fluid and replace it with a right and clean fluid.
• Replace the faulty powertrain control module or transmission control module. 

To do all this, you will need few high-quality auto parts such as Transmission control module, Digital voltmeter, Powertrain control module Transmission fluid pressure sensor, Automatic transmission module, PCM, ECM 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.

It is essential to diagnose this fault code. Here are some steps which a mechanic should follow for diagnosing the problem that triggered a P0845 code to be stored:

To diagnose this error code, you will need and advanced scanner, digital volt/ohmmeter, manual pressure gauge, a hydraulic pressure diagram, and a manufacturer's wiring diagram to properly diagnose a P0845 trouble code. Once you get hold of all these equipment’s you will need to follow the following steps:

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 P0845. 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 P0845 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 P0845 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 P0845 Code

Few of the common mistakes that you can commit while diagnosing this P0845 generic obd codes are listed as follows:

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