Fix P0705 Obd2 Code: Transmission Range Sensor Malfunction

If your car is displaying the P0705 obd2 code, don’t panic! This code means a problem with the gear selector sensor. This sensor monitors what gear the transmission uses is facing an issue and sets a code in engine control (ECM). 

P0705 Code Definition

P0705 code is a check engine light that appears when the transmission has a problem. The problem is signaled by the CEL being illuminated or by a P0705 code sent to the Engine Control Module (ECM). Also, it is a generic powertrain code that applies to almost all car models. 

P0705 Code Meaning

When the p0705 code is triggered, the transmission control module or ECM doesn’t see what gear is engaged by the vehicle’s transmission. The transmission range sensor’s purpose is to tell the TCM to ECM when to change the shift lever. It also detects the selector lever position when the shift lever is in N or P.

 In short; if the TCM or ECM can’t verify that the transmission control is neutral or park, it doesn’t allow the vehicle to start. A fault code for the malfunction is stored in the control module. This fault code is displayed on the Check Engine Light as code p0705.

OBD-II Code P0705: Symptoms, Causes & Diagnose

Causes of p0705 Engine Code

The most likely reason is a faulty range switch that is open or short within the component. In this situation, the transmission range switch sensor receives the correct input from the driver but cannot properly communicate it to the ECM. If it is out of calibration, it may send a wrong or no signal to the computer, thus identifying gear position. 

Also, sometimes, the range switch can be slightly moved to cause a switch misalignment. Besides that, if the transmission fluid is low or contaminated, it might cause difficulties in the valve body that controls gear shifting, resulting in a P0705 fault. 

The other reasons include:

• Faulty TCM or ECM
• Defective or faulty range switch
• Switch misalignment 
• Issue within the valve body
• Contaminated transmission fluid
• Poor transmission fluid
• Problem with transmission range switch

P0705 Engine Code Symptoms

Here are a few of the symptoms of the p0705 code:

1. Check Engine Light: The p0705 code is displayed in the P/N column of the ECM. This is the indication that there is an issue with the transmission. It will illuminate while driving if the transmission control has a fault.
2. No start (park or neutral): The vehicle cannot be driven when this fault occurs since it will not start.
3. No dash indicator: The P0705 code won’t display on the vehicle’s dashboard.
4. Erratic shifting: Here, the transmission performs erratically during shifting. For example, the car should be in “drive” but suddenly shift into “reverse”.
5. No Reverse lights: If your transmission is not reverse-driven, there will be no reverse lights.
6. Trouble shifting: When the vehicle cannot normally drive, for example, when it is too difficult to shift into drive or reverse, this may trigger the p0705 code.
7. Having to put the vehicle in a neutral position (N) to start: The vehicle has to be in a neutral shift position due to the sensor failure or a faulty component. The Neutral position can also be named pressure switch, gear selection switch, and PRNDL input switch. 
8. Malfunction Indicator Lamp: The warning backup lights may be on, and the check engine light will flick once, or they may fail to function at all.

How to Diagnose the P0705?

To run a diagnostic, you should start by checking the transmission control condition and fluid level. If it is just right, then you should inspect the electrical connection on the TRS by checking for ground specs or power. But, if the switch is mounted outside, then there might be moisture or debris in the connector causing the problem.

Also, check if the electrical connection is good, and check the ground or volt reference. Get a wiring schematic to ensure that the readings and wiring harness are correct. Also, shift between different gears to notice all the inputs and outputs. 

Depending on your vehicle, the range switch (variable resistor, pressure) can be tested using a digital multimeter. Voltage changes or resistance in circuits can easily be checked with a multimeter. An auto-ranging multimeter will be your best choice for diagnosis if all sensors pass. 

If you can’t diagnose it, you can take your vehicle to the auto repair shops, as they will take their diagnosis time to check this code according to your engine type. They will use a professional code reader such as Autel, Foxwell, and other diagnostic codes to diagnose properly. 

Tools you need to diagnose p0705:

For testing the range switch, you will need a multimeter and a wiring schematic. The wiring schematic will help you determine the range switch’s operation and what signal is supposed to be provided from the range switch to ECM.

What are the common mistakes to avoid when diagnosing the p0705 code?

Here are a few of the common mistakes you should avoid:

• Don’t change transmission fluid yourself without a proper technical education since it is an expensive mistake. 
• If you are not skilled enough to understand the result don’t scan transmission codes. 
• Do not clear codes without removing the source of the problem.
• Avoid using generic scan tools unless you have adequate technical skills. 
• Do not ignore bad sensor readings since they only lead to more serious problems.

How to fix the p0705 obd2 code?

First, you need to replace a defective switch with proper alignment. Also, you need to learn the adjustment procedure if you want to do it yourself.

After that, check the damaged wires and fix any broken wires. In the case of low fluid, a proper flush is required to fix this issue only if it hasn’t caused excessive damage.

Moreover, use a heated flush machine to remove all the dirty fluid; otherwise, the debris will stay in the engine, and you may face this error code again.

The other fixes include:

• Repair an open/short in the TRS circuit.
• Replace a faulty TCM and ECM.
• Replace the transmission fluid and filter.
• Adjust the linkage connected to the gear shifter.

FAQ

How to avoid the p0705 diagnostic trouble code?

To prevent the car from breaking down and causing an engine light or warning code to appear, you should regularly change the ATF or transmission fluid.

Can I drive with a P0705 code?

If you see the engine light flashing or any warning code or engine code on your dashboard, never ignore them. You should have them checked to avoid the risk of further damage or a breakdown. However, you can drive with the p0705 code. Fix error code p0262

What is the severity of the p0705 code?

The p0705 fault is considered minor. However, it might lead to a major problem in the long run. Some of the symptoms include rough shifting, engine lights, bad transmission fluid reading, and more.

How much does p0705 cost?

The cost depends on the problem’s complexity. It could be costly if the malfunctioning range switch has damaged the engine. The cost of repair includes the price of relevant parts. You can visit auto shops or for cost estimates.