How To Fix P0802 OBD2 Code?

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How To Fix P0802 OBD2 Code?
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P0802 is among the most typical OBD code problems discovered in cars and trucks with a computer system. This kind of code is the main trouble code, which implies it can often be caused by a significant problem. In all possibilities, this means that the car’s powertrain has to be brought back to its initially designed specs.

What is the P0802 Error Code?

What is the P0802 Error Code?

The P0802 OBD 2 Error Code is among the standard OBD-II codes. It’s generally caused by a fault in the power terrain known as Transmission Control System MIL Request Circuit/Open, which triggers the engine computer to believe it has actually lost an important parameter. Maintenance Indicator Light (MIL) lights up due to this error and it can also trigger the Power Control Module (PCM) error as well.

It is a serious error and if unsure you should take your vehicle to the nearest mechanic as soon as possible. Luckily in this article, we are going to share the required information you need to determine the root cause of the issue and lay out a course of action.

OBD-II Code P0802: Symptoms, Causes & Diagnose

Symptoms your car may have P0802 Error:

If you do not own an OBD 2 scanner, we recommend you to get one, however, there are still some tell-tale signs that your vehicle may be coming across a P0802 error. Your vehicle might be affected by the P0802 issue, following are the Symptoms your car may have P0802 Error:

  • MIL lights up on your dashboard.
  • Your vehicle is not shifting gears properly.
  • There is an abnormal sound detected while accelerating your vehicle, particularly in 3rd gear or lower.
  • There is a significant delay when you press the accelerator.
  • A check engine light won’t light up even you are experiencing issues.

Note: Although these symptoms suggest P0802, it doesn’t mean that your vehicle’s powertrain has actually been affected by the problem. Many other codes and OBD 2 system malfunctions may lead to issues in transmission or shifting gears. You need to get a professional to check your car before you can decide whether it is affected by this code.

What are the causes of the P0802 Error?

The P0802 OBD 2 Code is triggered by different variables. You must not just look into the car’s components for this code. The following are some of the most common causes that may lead to the P0802 error code:

  1. Transmission Control System MIL Request Circuit/Open: If you have actually already changed your car’s transmission fluid or have one replaced, there is a higher chance of this part getting weakened. A problematic TCM will trigger this error to happen, so you must get it replaced in case of malfunctions.
  2. Transmission Control System MIL Request Circuit Low Voltage: The most usual cause for this is the introduction of air or dust into the system. If your vehicle has actually just had its transmission fluid changed and the seal was not appropriately cleansed, this might also cause a P0802 issue.
  3. Driver’s Request Circuit/Open: This automobile error may be caused by a broken wire in the transmission solenoid or poor connections for any of the gears inside the car. The car will have to be checked as soon as possible to determine where the problem truly lies.
  4. Driver’s Request Circuit Low Voltage: A P0802 code is typically caused by a weak electrical connection and also faulty solenoids, which lead to the circuit not providing enough voltage for communication with the car’s computer system. Cleaning up this issue may quickly fix your problem.
  5. Open in Driver’s Request or Circuit: The car’s main transmission board, control unit, or wiring might be at fault. Your vehicle will need to be checked with an OBD 2 scanner.
  6. Transmission Control Module Time-Out Malfunction: A faulty PCM can also lead to this error code, which means the module is not able to communicate with the TCM in your car.
  7. Transmission Range Sensor Circuit Malfunction (PRNDL Input): The vehicle’s primary transmission will need to be checked immediately if the P0802 code is triggered, as this might indicate that something is triggering your PCM to believe there is a problem with the PRNDL input circuit. This error can be caused by a faulty range sensor, so you must get it serviced for this to be resolved.
  8. Transmission Range Sensor Circuit Low Voltage/Short to Ground or Open: A P0802 error can also be caused by problems in the transmission range sensor circuit, which is the reason why it has to be checked out immediately if you receive this code on your vehicle.
  9. Transmission Range Sensor Circuit High Voltage/Short to B+ : Another cause for the P0802 OBD 2 Error is a faulty transmission range sensor circuit, which will need to be looked into and if necessary, change it in order to solve this issue efficiently.
  10. Transmission Fluid Temperature Sensor #1 Circuit Malfunction (Temperature Sensor #1): If the transmission fluid temperature sensor is faulty, it will trigger this P0802 code to be on, which means that you need to fix the issue before it causes any more damage. You can check your car’s manual for more information on how to get this fixed, as well as check an OBD 2 scanner to determine where the problem lies.
  11. Transmission Fluid Temperature Sensor #2 Circuit Malfunction (Temperature Sensor #2): If your car is affected by this P0802 OBD 2 code, it shows that there is an issue with the second temperature circuit in your vehicle’s transmission. You will need to get it checked before anything else.
  12. Transmission Fluid Temperature Sensor #1 Circuit Range, Performance or Voltage Malfunction: This error is caused by problems with the first temperature sensor in your car’s transmission system. The part will have to be checked as quickly as possible if you want to prevent serious damage from taking place.
  13. Transmission Fluid Temperature Sensor #2 Circuit Range, Performance or Voltage Malfunction: The second temperature circuit in your car’s transmission system will need to be assessed if the P0802 code is present. Fixing this issue quickly is important.
  14. Transmission Fluid Cooler #1 Circuit Low Input (Limp Home, Stuck Off): A problem with the first fluid cooler in your vehicle’s transmission system will also be a reason for the P0802 OBD 2 code to appear. The car will have to be checked out before any other problems occur.
  15. Transmission Fluid Cooler #1 Circuit High Input (Stuck On): Another cause cooler in your car’s transmission system might be the cause of your P P0802 code, which will have to be checked as soon as possible.
  16. Transmission Fluid Cooler #2 Circuit Low Input (Limp Home, Stuck Off): Your second fluid cooler in your vehicle’s transmission will need to be looked at if you receive the P0802 code constantly.

How to Diagnose the P0802 Code?

The first thing you need to do is determine if the P0802 code is accompanied by a check engine light on or not. If so, this will help discern where your car’s problem lies and what needs to be done. Here are some steps you can take:

  • Pull out your car’s OBD II trouble codes. This can be done by using an OBD II scanner. Doing it yourself is the best option because you can do this for free.
  • Locate P0802 in the list of trouble codes. If it isn’t there, then your car’s code reader could possibly be broken or not connected properly to your car. If P0802 is shown, write it down.
  • If the P0802 code isn’t accompanied by a check engine light, then you can assume that your car’s engine is okay for now. Make sure to still get the underlying problem fixed though because this P0802 OBD 2 error is likely to reappear after some time.
  • If there really was a check engine light being displayed, you should then get a small amount of time spent on checking the car’s fuel cap to see if it was put on properly.
  • The next order of action is to check out your car’s oxygen sensors and also have the catalytic converter checked because one or both these parts might be broken. You need to also check the engine’s fuel injectors.
  • If you’re pretty sure that everything else is okay, then chances are this P0802 error code was caused by some loose wiring or something wrong with the car’s computer system. You should have your mechanic take a look at it if it is so because an internal problem with your car is always the hardest to detect.
  • If you’re sure that the computer system is fine, then this could mean that it was either a loose wiring or something wrong with your car’s transmission. You need to check that out too. Even if your mechanic says everything is okay, it still doesn’t hurt to double-check yourself and make sure there is no problem at all.

A common mistake you must avoid when diagnosing the error code P0802:

A vehicle’s computer is very smart but at the same time can trigger a more severe code for a smaller issue. Just like a Check Engine line turning on for a loose Fuel Cap you may experience P0802 for something less serious. If your vehicle is not showing the serious signs mentioned above then before heading to the mechanic and agreeing to pricey repairs, check your vehicle’s wiring. Especially the harnesses at the transmission end. Check for loose and faulty wires. Identify if a bare wire is touching the car’s body or coming in contact with rainwater. These are the common mistakes you could avoid and help you save money on costly repairs and also being stranded on the roadside.

Tips for further avoiding the P0802 obd2 error code:

Taking care of your car and proper maintenance can help you avoid all costly repairs. As with any broken part, you can help yourself to never encounter the P0802 error code. These are some tips for further avoiding the P0802 obd2 error:

  • Always take care of your car properly.
  • Keep your receipts and document every time you visit the mechanic.
  • When driving, drive smoothly and slowly because sudden acceleration can also damage the car’s transmission.
  • Get rid of all old fluid in your transmission especially if it is dark or black in color. This may cause a P0802 error. Do not forget the transmission filter as well.
  • Never ignore any unusual change in your car’s sound. Check for engine warning light issues too. They usually help you identify a problem with your vehicle ahead of time before it gets serious and more expensive to fix.
  • Get rid of faulty belts and hoses so that they won’t cause any P0802 trouble code to pop up.
  • Change your oil at the right time interval and don’t forget to replace your air filter often.