P0705
Transmission Range Sensor A Circuit (PRNDL Input).
- Generic
- Powertrain
- Generic code
- Medium severity
How this code is built
- P
- SystemPowertrain
- 0
- Defined bySAE, the same on every car
- 7
- AreaTransmission
- 05
- FaultThe specific fault in that area
What it means
P0705 is the generic code for a fault in the Transmission Range Sensor 'A' circuit, which tells the control unit which gear position (P, R, N, D and so on) the selector is in. The transmission or engine control unit sets it when the signal from the range sensor is missing, out of range or does not make sense for the selector position or vehicle behaviour. Exact sensor design and fault logic vary by manufacturer and transmission, so check model-specific information.
Symptoms
- Gear selector position not shown or wrong on the dash display
- Engine will not start in Park or Neutral, or starts in other gear positions
- Harsh, delayed or no gear engagement
- Transmission stuck in one gear or in limp mode
- Reversing lights not working or staying on
- Gearbox warning light or malfunction indicator lamp on
Possible causes
- Faulty or misadjusted transmission range sensor (neutral safety or PRNDL switch)likely
- Damaged, corroded or loose wiring or connector at the range sensorlikely
- Selector cable or linkage out of adjustment, worn or loose so the sensor and the gearbox are not in the same positionpossible
- Water or fluid contamination inside the sensor or its connectorpossible
- Dirty or degraded transmission fluid, or a fault in the valve body or manual valve, affecting the readings or the gear engagement on some designspossible
- Fault in the transmission control unit or its power and earth supplyrare
How to diagnose
- Read all stored codes and freeze frame data, noting whether the fault is current or intermittent and any related codes
- Check the selector position shown on the dash and in live data against the actual lever position, moving through every position slowly
- Inspect the range sensor wiring and connector for damage, corrosion, water ingress, chafing and poor pin tension
- Check the selector cable and linkage for wear, looseness and correct adjustment against the manufacturer's procedure
- Check the transmission fluid level, condition and smell, following the model-specific procedure as some gearboxes are sealed
- Test the sensor supply, earth and signal circuits for continuity, shorts and voltage drop using the wiring diagram for the vehicle
- Wiggle test the harness with live data on screen to find intermittent dropouts
- Check the control unit power supplies and earths, and for any relevant software updates or technical bulletins for the model
How to fix
- Repair or replace damaged wiring, and clean or replace corroded connectors
- Adjust the selector cable and range sensor to the manufacturer's specification
- Replace the transmission range sensor if it is faulty or cannot be adjusted correctly
- Service or replace contaminated transmission fluid and filter where the design allows, and rectify any leaks letting water in
- Repair or replace the valve body or manual valve linkage if found faulty, as per model-specific diagnosis
- Repair control unit supply or earth faults, and replace or update the control unit only if confirmed faulty or a known calibration issue applies
Can I keep driving?
The car may be driven carefully a short distance if it starts and engages gears normally, but get it checked soon as it may go into limp mode, fail to start or select gears unpredictably. Do not drive if the gear position is unreliable or the car moves unexpectedly.
Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.