What does it mean?
This diagnostic trouble code (DTC) is a generic powertrain code, meaning it applies to vehicles equipped with OBD-II. Although generic, specific repair steps may vary by make/model.
It is a powertrain diagnostic trouble code (DTC) for the transmission control system. It is a type “C” DTC that does not trigger the check engine light but may cause the overdrive (O/D) or D4 indicator to flash. Only emission-related codes trigger the check engine light.
The transmission range sensor operates by receiving a voltage signal. It is changed or rerouted based on the gear lever position. In the DTC description, it indicates a low state in the circuit. This refers to a low or no voltage signal returning to the PCM. Refer to the diagram in the diagnostic/repair section below.
Example of an external transmission range sensor (TRS):
Transmission Range Sensor TRS (external type)
Symptoms and severity of the code
The engine may not start due to the park/neutral switch, which is internal to most transmission range sensors. There may be irregular shifting or even the possibility of starting in gear. There could also be a lack of power due to the transmission controls being in “limp home” mode.
There is certainly a safety factor to consider with this code, and it should be repaired as soon as possible.
The possible causes for this code being set are as follows:
- Faulty transmission range sensor
- Open or shorted wiring
- Misadjusted transmission range sensor
- Faulty PCM
- Diagnostic and repair procedures
- To diagnose this code, we first need a basic understanding of two things:
1. What is an open circuit?
An open circuit is a circuit that does not form a complete loop from the battery negative to the battery positive. For example, when a light bulb stops working because the filament breaks in two, the circuit would be open at the broken filament.
2. What is a short circuit?
A short circuit occurs when the battery negative comes into contact with the battery positive without any type of load between them. In other words, there must be a component (e.g., a light, motor, sensor, etc.) in the circuit. A short circuit is like dropping a key on your car battery, and it touches both terminals and sparks. This is called a direct short.
Now, with basic circuit 101 out of the way, refer to the diagram below. An open circuit at point A, B, or C would cause low voltage at the PCM. A short circuit at the same points would cause a blown fuse and again low voltage at the PCM. Both conditions will set DTC P0707.
To determine the exact cause of the DTC, simply check the voltage at points A, B, and C. If there is voltage at A and B but not at C, suspect a faulty range sensor. If there is voltage at C, suspect shorted wiring or, in rare cases based on my experience, a faulty PCM. If there is voltage at A, check only the fuses.
Related transmission range sensor codes: P0705, P0706, P0707, P0708, and P0709.