P0707 Transmission Range Sensor A Circuit Low Input
OBD-II Trouble Code Technical Description
Transmission Range Sensor “A” Circuit Low
What does that mean?
This diagnostic trouble code (DTC) is a generic powertrain code, which means that it applies to OBD-II equipped vehicles. Although generic, the specific repair steps may vary depending on make/model.
This is a generic powertrain diagnostic trouble code (DTC) for the transmission control system. It is a type "C" DTC that does not cause a check engine light, but may cause the overdrive (O/D) or D4 indicator to blink. Only Emission related codes cause a check engine light.
The transmission range sensor works by receiving a voltage signal. Changing or rerouting it according to position of the gear shifter. In the DTC description it indicates a low condition in the circuit. This is referring to low or no voltage signal returning to the PCM. Refer to the diagram in the diagnosis/repair section below.
Example of an external Transmission Range Sensor (TRS):
TRS image from Dorman
Symptoms & Severity of Code
The engine my exibit a no start condition due the park/neutral switch which is internal on most transmission range sensors. It could have erratic shifting or even possibly start in gear. It could also have a lack of power due the transmission controls being "limp home" mode.
There is certainly a safety factor to be considered in association with this code and should be repaired as soon as possible.
Causes
Potential causes for this code to set are:
Diagnostic and Repair Procedures
To diagnose this code we must first have as a basic understanding of two things:
1. What is an Open Circuit?
An open circuit is a circuit that does not make a complete loop from battery negative to battery positive. For example, when a light bulb stops working because the filament broke in half, the circuit would be open at the broken filament.
2. What is a short circuit?
A short circuit is when batter negative comes in contact with battery positive without some type of load in between the two. In other words there has to be a component (i.e. a light, a motor, a sensor, ect.) in the circuit. A short circuit is like dropping a wrench on top of your car battery and it touches both terminals and makes sparks. That is called a direct short.
Now with simple circuit 101 out of the way refer to the diagram below. An open circuit at point A, B or C would cause low voltage to the PCM. A short circuit at the same points would cause a blown fuse and again low voltage at the PCM. Both of these conditions will set DTC P0707.
To verify the exact cause of the DTC simply check for voltage at point 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 my Experience, upon rare occasion, a faulty PCM. If there is voltage at A only check the fuses.
Related Transmission Range Sensor codes: P0705, P0706, P0707, P0708, and P0709.
Need help?
Let us fix your problem. You are most welcome our diagnosis experts have in most cases the knowledge and skills to find the cause of the error code p0707 and to solve the problems.
Make an appointment for diagnosis
"Delete Error Code Permanently, Disable DTC Error Code Function for p0707 in the ECU"
In extreme cases, we even have the option to permanently remove the specific DTC p0707 and disable the function of the specific error code in the ECU. All other fault code functions will then continue to work to protect the engine. This is different from clearing an error code with a diagnostic device. We have the option to permanently remove the function of the specific error code, so that it never comes back. Also emergency running that occurs on the specific error code can be solved in most cases.
Of course we prefer to first try to solve the cause of the error code, but sometimes the only solution is to permanently disable the DTC function of p0707.
