A P0705 code is a generic powertrain code that can be triggered in select vehicles built from 1996 onward. This OBD-II code may present common symptoms in different types of vehicles, but diagnosis and repair may vary for each specific make and model.
What Does the P0705 Code Mean?
Diagnostic trouble code (DTC) P0705 code stands for “Transmission Range Sensor Circuit Malfunction (PRNDL Input).” It is triggered when the transmission range sensor cannot send data or provides erroneous input to the transmission control (TCM) or powertrain control (PCM) modules.
The transmission range sensor may also be called the neutral safety switch or PRNDL input. Located outside the transmission box or on the valve body, its job is to communicate the current gear selection or shift lever position with the TCM or PCM.
The information it collects is used by these vehicle’s computer systems to control functions, such as transmission mainline pressure. In some vehicles, backup lights activate through the signals received from an external transmission range sensor.
What are the Possible Causes of the P0705 Code?
There are two scenarios that could cause a vehicle’s OBD-II system to log a P0705 code. The first is when the TCM and PCM do not receive any information from the transmission sensor at all.
The second is when these modules receive an irrational input from the sensor.
An example could be if the vehicle is running at 70 mph, but the sensor signals the TCM that the car is in park. Likewise, this diagnostic trouble code will trigger if the sensor sends signals that indicate that the vehicle is in multiple gears at the same time.
Here are the common problems that can cause missing/faulty readings from the transmission range sensor:
- Malfunctioning transmission range sensor (PRNDL input)
- Issues with the transmission range sensor circuit, such as damaged wires or poor connections
- Low levels of transmission fluid
- Clogged hydraulic passages because of contaminated transmission fluid
- Defective valve body
- Defective shift linkage
- Faulty TCM or PCM
What are the Common Symptoms of the P0705 Code?
A P0705 trouble code may cause performance problems that would be noticed by the driver. Below are some signs that you should look out for:
- Check Engine Light is on or blinking
- Rough or delayed shifting
- Failure to put the vehicle into gear
- Erratic dash indicators (PRNDL)
- Reverse lights don’t switch on
- Vehicle starts with the gear selector in a position other than park or neutral
Occasionally, a malfunction in the transmission range sensor circuit may occur without any adverse effects that affect the drivability of your vehicle.
How to Diagnose the P0705 Code
There are a lot of possible causes that could trigger the P0705 code, so diagnosis can get a little tricky especially if you’re not very car-savvy. This is why most people just leave the job to their mechanic.
However, you can still do the job yourself with the help of a detailed guide. Below is a helpful video with more information to help you diagnose the P0705 code:
How to Fix the P0705 Code
There’s no one-size-fits-all solution for the P0705 code—just like with most OBD-II codes. Most people simply take their cars to their mechanics and leave the job to them. However, if you feel confident in your DIY skills or are looking to learn more about auto repair, then you can try taking the task on yourself.
To figure out the appropriate fix for the P0705 code, do some research on forums and other similar platforms to see what other car owners (who own the same vehicle, of course) have done to successfully clear the code.
It’s important to note that different vehicles may involve different fixes. For example, replacing the transmission range sensor has been confirmed to work in fixing a P0705 code on a 2011 Ford F-150, XL 5.0L, V8, but doing the same thing may not work for your vehicle.
And remember—when doing any DIY work on your vehicle, make sure to consult repair manuals and credible online guides. You can also get an ALLDATA single-vehicle subscription, which should give you the information you need for this and any other future repairs your car may need.