What are the P0705 Code Symptoms and Causes? | How to fix P0705 Code?

The P0705 code is a generic trouble code that can show in only some specific cars manufactured in 1996 and onward. This code triggers as the transmission range (TR) sensor of your vehicle doesn’t send data or sends insufficient data to the powertrain control module (PCM) or transmission control module (TCM). This article explains the symptoms and causes of the P0705 code.

P0705 Code Definition

P0705 code stands for “Transmission Range Sensor Circuit Malfunction (PRNDL Input).”

What does the P0705 code mean?

The P0705 code indicates that your powertrain control module (PCM) has received an input error from the Transmission Range Sensor (TRS).

The transmission range sensor is also known as a pressure switch, Park Neutral Position switch (PNP), gear selection switch, or PRNDL input switch. The function of the Transmission Range Sensor is to tell the PCM or TCM the position of the shift lever.

P0705 code

The TRS is most commonly located on the outside of the transmission; however, some of them are located inside of the transmission on the valve body.

The DTC P0705 is set when the powertrain control module doesn’t get sufficient input from the TRS. This code may also trigger if the PCM is getting an input that is logically impossible. For example, if your vehicle is traveling at 50 MPH, but the TRS is telling the PCM that it is in Reverse, then your PCM will immediately trigger the code P0705.

In some cases, the TRS fails until it tells the PCM that it is in multiple gears at the same time. In this case, code P0705 will trigger.

Working of Transmission Range Sensor

The primary function of transmission range sensors is to record the transmission speed. The transmission speed is needed by the control unit for regulating the shifting pressure while shifting gears and for deciding which gear requires to be engaged at which point.

Working of Transmission Range Sensor

A PCM or TCM can detect when the clutch is engaged and disengaged. It can also read the RPM. After obtaining all these pieces of information, a TCM performs a certain function based on user feedback.

Some PCMs have the ability to store one’s driving habits in internal memory and can apply the memorized information to one’s transmission performance.

Symptoms of the P0705 Code

A P0705 trouble code may cause performance problems that the driver would notice.

Symptoms of P0705 Code

Below are the common symptoms of the P0705 code:

  1. Check Engine Light illumination
  2. Rough shifting
  3. Vehicle starts with the gear selector in a position other than park or neutral
  4. Delayed shifting
  5. Failure to put the vehicle into gears
  6. Erratic dash indicators (PRNDL)
  7. Reverse lights don’t switch on
  8. Harsh engagement into gear

Causes of P0705 Code

  1. Defective shift linkage
  2. Contaminated transmission fluid
  3. Corrode, worn or damaged transmission range sensor wiring or connectors.
  4. Misadjusted TRS
  5. Damaged PCM
  6. Faulty or damaged TRS
  7. Damaged transmission valve body

Read More: Causes and Symptoms of Transmission Fluid Leak

Common mistakes when diagnosing the P0705 code

As you see the P0705 code, inspect your transmission fluid first. Contaminated or dirty transmission fluid can create all kinds of phantom problems with your transmission that store any number of OBDII codes. Start with a fluid check before you end up doing any unnecessary repairs.

How to diagnose the P0705 Code?

You must have the following tools to fix or diagnose the P0705 code:

  1. Electrical Contact Cleaner
  2. Diagnostic OBD Scan Tool
  3. Auto Repair Manual
  4. Multimeter
  5. Basic Hand Tools

Follow the below-given steps to diagnose the P0705 code:

  1. Look for other codes with your OBDII scanner. If there are other issues to repair, do that first.
  2. Clear the Check Engine Light.
  3. Check the new freeze frame data to find the new codes.
  4. If you have an internal transmission range sensor, you might need the help of a shop to go further. These are much harder to diagnose.
  5. You can reference the service manual with an external sensor to ensure it is properly adjusted.
  6. Inspect the wiring of the TRS. Repair any damaged wires or re-establish the connection if there is a problem.
  7. Replace the transmission range sensor if you can’t find any other issues. 

How serious is the P0705 Code?

  • It is not too damagingly serious, except that you won’t be able to pass inspection with a Check Engine Light.
  • It may lead to no start condition along with the Check Engine Light.
  • Your car can go into emergency mode and cannot exceed a speed of over 40 MPH.
  • It may lead to shifting issues.

What repairs can fix the P0705 Code?

Here are some of the major common fixes to consider:

  1. Clean and re-establish the connection of the external TRS
  2. Replace the TRS
  3. Replace defective wiring to the transmission range selector circuit
  4. Adjust shift linkage
  5. Replace valve body
  6. Replacing a faulty TCM or ECM
  7. Changing the transmission fluid
  8. Replace the transmission filter

P0705 Code Repair Cost

When it comes to making repairs associated with the P0705 code, one or more of the below repairs may be needed to solve the underlying issue. For each possible repair, the estimated cost of repair includes the cost of the relevant parts and the cost of labor required to make the repair. 

Transmission Range Sensor Adjustment$90
Valve Body$410 to $1100
Transmission Range Sensor$90 to $360
Transmission$1700 to $4600
Tail Lamp Assembly$190 to $2100
Wiring replacement/repair$90 to $1100

FAQ Section

What happens when your transmission range sensor goes out?

The Transmission Range Sensor tells the PCM the position of the transmission shifter. The PCM uses this information to control which gears of the transmission to enable or disable. When the TR sensor fails, it can cause wrong gear starts, no upshifts, or what feels like a falling-out-of-gear condition.

Can you drive with a P0705 Code?

The severity level of the P0705 code is considered to be moderate. Extended driving with this code can badly damage the internal parts of your car engine. You can most commonly drive your vehicle with the P0705 code, but with significant performance problems; therefore, it is strongly not recommended.

How long does it take to change a TR sensor?

It takes about 2-3 hours for the transmission range sensor to be replaced by a professional. If the sensor is in the transmission, the repair may take longer as the mechanic will have to disassemble and reassemble it.

Is the transmission range sensor the same as the neutral safety switch?

The Neutral Safety Switch and the Transmission Range Sensor are protection devices used to prevent starter operation in all gears other than Park and Neutral. The sensors are a member of the starter control circuit and inform the TCM of the current gear selection.

How many transmission speed sensors are used in a car?

A car has two speed sensors: the ISS and the OSS, working together to show the transmission data to the car’s powertrain module. The ISS sensor monitors the input shaft’s speed. If these sensors get misaligned, the operation of the transmission system will be affected.

How much is it to replace a transmission sensor?

The average transmission position sensor replacement cost is between $265 and $325. Labor costs are estimated between $140 and $178, while parts are priced between $122 and $138.

Can an ABS sensor affect transmission?

Yes, a faulty ABS sensor can cause the transmission to act weirdly or shift improperly. The ABS sensor is a wheel speed sensor mounted on the hub of each wheel to report the speed of all four wheels individually to the ECU.

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