By iCarsoft Team
P1705 Code Fix: Transmission Range Sensor Circuit (Honda)
Code P1705 is a Honda manufacturer-specific code for a fault in the transmission range sensor (TRS) circuit — the switch that tells the computer which gear you've selected. On Hondas it usually means a short in the range-switch circuit, and it can leave your car hard to start, stuck in one gear, or showing a flashing "D" light. This guide explains what P1705 means on a Honda (its meaning differs on other brands), its symptoms and causes, how to diagnose it, realistic costs, and how to fix and clear it.
If your Honda won't start, is stuck in gear, or is flashing the "D" indicator with the Check Engine Light on, a scan may return P1705 — a transmission range sensor circuit fault. The range sensor (also called the transmission range switch or neutral safety switch) reports your gear position to the computer; when its circuit shorts or opens, the computer no longer knows what gear you're in. The reassuring news is that on Hondas this is usually the switch or its wiring — not the transmission itself.
What Does P1705 Mean?
Your automatic transmission has a transmission range sensor (TRS) — also called the range switch or neutral safety switch — that reports the shift-lever position (P, R, N, D, L) to the engine and transmission control module. The computer uses that signal to allow starting only in Park or Neutral, turn on the reverse lights, and choose the right shift strategy. On a Honda, P1705 is set when the ECM/TCM sees an invalid signal from that range-switch circuit — commonly a short to ground.
One important detail: P1705 is a manufacturer-specific code (the "P1" family), so its meaning varies by brand. On Honda and Acura it points to the transmission range switch circuit; on Nissan and Infiniti the same code refers to a throttle-position signal lost over the data bus; and on some older Toyotas it points to a clutch-speed sensor. This guide focuses on the Honda definition — and because P1705 is manufacturer-specific, it isn't covered by the generic SAE code list, so always confirm the exact definition for your vehicle.
On Hondas, P1705 frequently appears alongside P0705 — the generic "Transmission Range Sensor Circuit (PRNDL)" code — and the two are essentially the same fault read by different scanners. If you see one, check for the other.
Symptoms of P1705
P1705 turns on the Check Engine Light — part of the OBD-II system overseen by the California Air Resources Board — and, on Hondas, often the "D" indicator. Watch for:
- Check Engine Light or a flashing "D" indicator on the dash.
- Difficulty shifting — or the vehicle stuck in one gear.
- No-start condition — the engine may crank only in Park/Neutral, or not at all.
- Reverse lights not working — the same circuit drives them.
- Erratic transmission behavior — unpredictable or harsh shifting.
Commonly Affected Vehicles
P1705 is most associated with Honda and Acura models — the Civic, Accord, Odyssey, and TL among them — particularly older automatics (roughly 1995–2005) where the range switch and its wiring wear or corrode. The same code appears on other makes too, but with a different meaning, so always confirm the definition for your specific vehicle.
The Most Common Root Causes (Ranked)
On a Honda, a P1705 lives in the range switch, its wiring, or how it's adjusted — rarely in the transmission itself.
| Likelihood | Cause | Why it happens |
|---|---|---|
| ~40% | Faulty transmission range switch/sensor | Internal wear or a short to ground makes the switch report an invalid gear signal. |
| ~25% | Damaged or corroded wiring/connectors | Corrosion or fluid intrusion in the sensor circuit interrupts the signal. |
| ~15% | Misadjusted range sensor | After transmission or shifter-cable work, a misaligned switch can't read gears correctly. |
| ~10% | Aftermarket remote-starter / alarm wiring | A poor install that taps the start or range circuit is a common Honda trigger. |
| ~10% | Blown fuse or ECM/TCM issue | Less common — a blown fuse or, rarely, a module fault in the circuit's control. |
How to Diagnose P1705
Diagnose P1705 by confirming the range signal follows the shifter, then checking the wiring before replacing the switch. A scanner that reads transmission live data — like the iCarsoft CR MAX or CR Eagle — makes this straightforward.
Step 1 — Scan & read codes. Confirm P1705 and any companion codes (P0705, P0700, P0715), and note the freeze-frame data.
Step 2 — Watch live PRNDL data. Move the lever P → R → N → D → L and confirm the displayed gear follows each position without dropouts; a mismatch points to the range switch.
Step 3 — Inspect the switch, connector & harness. Check the range switch on the transmission and its connectors for damage, corrosion, or fluid intrusion.
Step 4 — Check aftermarket wiring. If the car has a remote starter or alarm, inspect its connections under the dash — a frequent Honda trigger.
Step 5 — Test the circuit. Check continuity and voltage against the service-manual spec; Honda pinouts and expected voltages are model-specific, so use the factory values.
Step 6 — Adjust or replace & clear. Adjust a misaligned switch or replace a faulty one, repair any wiring, clear the codes, and confirm the engine starts only in Park or Neutral.
Repair Cost Breakdown
On a Honda, P1705 is usually a moderate fix — the switch and wiring, not the transmission. Figures below reflect typical 2025–2026 US rates.
| Repair | Typical Cost (USD) |
|---|---|
| Professional diagnosis | $75–$150 |
| Transmission range switch/sensor — part | $50–$150 |
| Switch replacement — labor | $100–$200 |
| Wiring / connector repair | $50–$150 |
| Fuse | Under $10 |
Good to know: a Honda P1705 repair typically lands around $150–$350 all-in. Catching it early matters — a failing range switch can leave you with a no-start and stranded.
Diagnose P1705 with the iCarsoft CR MAX or CR Eagle
A basic reader confirms P1705 but can't show whether the range switch is actually reporting the right gear. The iCarsoft CR MAX and CR Eagle read transmission live data, so you can watch the PRNDL signal track the shifter and rule out the transmission before replacing parts.
- Live PRNDL / gear data — confirm the displayed gear follows the lever.
- Full-system access — read ECM and TCM codes, including companions like P0705.
- Circuit and wiring checks to separate a switch fault from a harness fault.
- Broad multi-brand coverage — Honda, Acura, and 200+ makes.
- Clear codes and confirm the repair once the car starts only in Park or Neutral.
Preventive Maintenance — Keep P1705 Away
- Inspect the range switch and its wiring — corrosion and wear are the usual triggers.
- Keep connections clean and secure — especially after transmission or shifter work.
- Have aftermarket starters/alarms installed properly — bad taps cause range-circuit faults.
- Address shifting irregularities early — before a no-start strands you.
- Follow Honda's maintenance schedule — including transmission fluid service.
Frequently Asked Questions
What does P1705 mean on a Honda?
It's a fault — usually a short — in the transmission range switch circuit, the switch that reports your gear position. On Hondas it often shows up as a no-start or a flashing "D" indicator.
Is it safe to drive with P1705?
Not advisable. You may be unable to start, get stuck in gear, or — in a worst case — the engine could start while in gear. Fix it promptly.
Is P1705 the same as P0705?
On Hondas, essentially yes. P0705 is the generic version of the same transmission range sensor circuit fault, and the two are often read together — diagnose them as a pair.
Does P1705 mean my transmission is failing?
Usually not. It's an electrical fault in the range switch or its wiring — not internal transmission damage — so it's typically a much cheaper fix.
Can an aftermarket alarm or remote starter cause P1705?
Yes. A poor install that taps the start or range circuits is a common Honda cause, so check that wiring before condemning the switch.
Bottom Line
On a Honda, P1705 means the transmission range switch circuit is sending an invalid gear signal — and because that switch is also your neutral safety switch, it can leave you with a no-start, a flashing "D," or non-working reverse lights. The good news is it's almost always the switch, its wiring, or its adjustment, not the transmission. Confirm with live data that the displayed gear follows the shifter using a capable tool like the CR MAX or CR Eagle, inspect the wiring (including any aftermarket starter), then adjust or replace the switch. Keep in mind P1705 means different things on other brands, so always verify the definition for your vehicle — then fix the cause, clear the code, and you're back on the road.
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