P0706 OBD-II Trouble Code: Transmission Range Sensor Circuit Range/Performance

P0706 Code Definition

The P0706 code is a generic powertrain code related to the transmission. This code is non-emission related. The transmission range sensor circuit is not communicating correct data to the engine control module (ECM). This code only applies to vehicles with an automatic transmission.

Codes related to the P0706 include:

• P0705: Transmission Range Sensor Circuit Malfunction (PRNDL Input)
• P0707: Transmission Range Sensor Circuit Low Input
• P0708: Transmission Range Sensor Circuit High Input
• P0709: Transmission Range Sensor Circuit Intermittent
• P0814: Transmission Range Display Circuit
• P0819: Up and Down Shift Switch to Transmission Range Correlation

What the P0706 Code Means

A transmission range sensor is also called a park/neutral switch or safety switch. The sensor communicates with the vehicle's transmission control module and ECM and is attached to the manual valve of the transmission.

The transmission range switch detects whether the selector lever is in park or neutral and sends the signal to the transmission control module. This is to ensure the vehicle on starts in the park and neutral position.

When a P0706 code appears, the transmission is not receiving clear data from the transmission range sensor. This mostly occurs when the vehicle is in motion and reads that the vehicle is traveling at a speed that does not match what the ECM sees as the current shift position (such as traveling at any speed when the transmission is reporting it is still in park or neutral).

What Causes the P0706 Code?

Several problems may cause a P0706 code including:

• Dirty or poor quality transmission fluid
• Damaged or defective park/neutral position switch
• Damaged or improperly adjusted park/neutral position switch
• Damaged or defective transmission range sensor
• Damaged, defective, or shorted wiring to the transmission range sensor
• Damaged or defective valve body
• Damaged or faulty manual shift valve linkage
• Shorted or open park/neutral position switch harness
• Bad electrical connection to the park/neutral position switch circuit
• Damaged or defective control cable
• Damaged or defective ECM (rare)

What are the Symptoms of the P0706 Code?

Symptoms of a P0706 code may include:

• A Check Engine or Warning Light may illuminate
• Poor shifting
• Decreased acceleration
• Inability to switch gears
• Poor fuel efficiency
• The vehicle may go into “limp” mode

How Does a Mechanic Diagnose the P0706 Code?

A mechanic may use several methods to diagnose a P0706 trouble code, including:

• Utilize an OBD-II scanner to check for a stored P0706 trouble code

• Visually inspect the range sensor and wiring harness for damage

• Visually inspect all wires and connectors related to the transmission range sensor and ECM for damage

• Determine if the vehicle will start while in the reverse shift position or drive shift position

• Clear codes, test drive the vehicle to see if code reappears

• Check for circuits continuity and resistance

Common Mistakes when Diagnosing the P0706 Code

At times, a P0706 code is the result of an engine misfire or driveline problem. Always check for any other stored codes that could be the ultimate cause of the problem before replacing parts unnecessarily.

How Serious is the P0706 Code?

Because the vehicle’s operation could suffer and the transmission may go into “limp” mode, the P0706 code is considered potentially serious, and it is recommended that you take your vehicle to your local mechanic for diagnosis and repair as soon as possible.

What Repairs can Fix the P0706 Code?

Several repairs can fix a P0706 trouble code and include:

• If necessary, flush and fill transmission fluid
• Repair or replace any damaged or faulty wiring or connectors
• Check battery voltage levels
• Repair or replace any damaged or defective circuits or connectors
• Repair or replace damaged or defective transmission range sensors
• Repair or replace a damaged or defective ECM (rare)
• Clear all codes, test-drive the vehicle, and rescan to see if any codes reappear

Need Help with a P0706 Code?

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