OBD codes / P0705
P0705
SeriousTransmission Range Sensor Circuit (PRNDL Input)
P0705 can be unpredictable — the car may not start, may not show reverse lights to drivers behind you, or may engage gears harshly. It's usually drivable once running, but a car that doesn't reliably know whether it's in Park or Drive deserves prompt attention. If the gear display acts erratic, get it looked at before relying on the car.
What this code means
The transmission range sensor (also called the neutral safety switch or PRNDL switch) tells the computer which position the shifter is in — Park, Reverse, Neutral, Drive, or Low. P0705 means that circuit is sending a faulty or missing signal, so the car may literally not know what gear you've selected. That causes some odd symptoms: the engine may refuse to crank because the computer can't confirm you're in Park or Neutral, the reverse lights may not work, and the dash may show the wrong gear or a flashing indicator. Common causes are a misadjusted or worn sensor, and wiring or connector trouble — including transmission fluid wicking up the harness into the connector. On some vehicles the sensor is a simple external switch on the side of the case; on others it lives inside the transmission. It's usually an electrical fix, not an internal transmission problem.
Symptoms you might notice
- Engine won't crank in Park (or only starts in Neutral)
- Reverse lights don't come on, or stay on in the wrong position
- Gear indicator on the dash is wrong, blank, or flashing
- Harsh or delayed engagement when shifting out of Park
- Check-engine light
What it costs to fix
Typical range: $80–$500 · about ~0.5–1.5 hrs of labor
| If the cause is… | Part | Labor |
|---|---|---|
| Transmission range sensor | $50–$300 | ~0.5–1.5 hrs |
| Adjustment or linkage correction | $0–$40 | ~0.3–1 hrs |
| Wiring / connector repair | $10–$120 | ~0.5–1.5 hrs |
Externally mounted range sensors are a quick bolt-on job at the low end. Some transmissions put the sensor inside the case, which raises labor considerably. Sometimes the fix is just cleaning the connector or re-adjusting the sensor — no part at all.
The price swings on which cause it turns out to be — so confirm the cause before paying. Diagnose P0705 for my exact vehicle →
Frequently asked
Why won't my car start with P0705?
The computer only allows cranking in Park or Neutral. If the range sensor can't confirm the shifter position, the starter may be blocked. A common workaround to reach a shop is trying to start in Neutral instead of Park — if that works, it points strongly at this sensor.
Why are my reverse lights not working?
On most vehicles the same range sensor circuit switches on the backup lights. A faulty sensor or wiring can leave them dead — or stuck on in the wrong gear. Fixing the sensor usually restores them.
Is P0705 an internal transmission problem?
Usually not. It's most often the external sensor, its adjustment, or the wiring — an electrical fix rather than mechanical transmission work. On transmissions where the sensor is internal, labor goes up, but it's still not a rebuild-level repair.
Can I drive with P0705?
Cautiously and short-term. The risks are practical: no-starts, no reverse lights, and possible harsh engagement or wrong-gear starts. It won't typically destroy the transmission, but it's the kind of fault that strands you at the worst time.
Seeing P0705 on your car? Get a diagnosis specific to your exact year, make and model.
Diagnose P0705 for my vehicleSymptoms that trigger P0705
Drivers who get this code often notice one of these — each has its own likely-causes and cost guide:
Related trouble codes
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Generic OBD-II reference. Manufacturer-specific behavior varies — confirm with a scan tool and, for safety-related codes, a professional inspection.