What it means
The transmission range sensor (PRNDL switch / inhibitor switch) signal is implausible — multiple positions active simultaneously, or no position recognized. Engine may refuse to start unless P or N is detected.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Transmission Range Sensor A reports the selected gear position, including Park, Reverse, Neutral, and Drive, to the transmission control system. P0705 sets when the PRNDL input is electrically invalid, such as when no position or conflicting positions are recognized, and the engine may not receive a valid Park or Neutral start signal.
Common causes
Most likely first.
- Range sensor misadjusted
- Range sensor failed
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
How to diagnose it
- With the vehicle secured, compare the dashboard gear indication with the actual selector position and note any missing or conflicting display.
- Read TCM and PCM codes plus live range-sensor data while moving the selector through each position, checking whether the reported position follows it consistently.
- Inspect the Range Sensor A connector and wiring for corrosion, loose terminals, damage, or fluid intrusion.
- Check sensor alignment and selector linkage adjustment using the manufacturer's procedure.
- If alignment and wiring are sound, test the range sensor's position outputs and circuit before replacing the sensor.
Common fixes
- Adjust Range Sensor A alignment or selector linkage if the indicated position is offset.
- Secure or clean a poor range-sensor connector contact.
- Repair damaged wiring in the PRNDL input circuit.
- Replace Range Sensor A if its position outputs remain invalid after alignment and circuit checks.
- Correct a verified fault in the TCM input circuit.
Can I keep driving?
Do not drive if the indicated gear does not match the selector or the transmission may engage an unexpected range. A faulty Park or Neutral signal can prevent starting; have the vehicle secured and avoid relying on it until the range input is reliable.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.