PowertrainP1721
CautionSeverity: Caution - get it checked when you can
Gear 1 incorrect ratio
Key terms: Control module: a small computer that runs one part of the car · Powertrain: engine, transmission and emissions
1What it means in plain English
The engine or powertrain control system has stored a fault that does not have specific guidance in this database yet.
2Common causes
- Sensor or actuator fault
- Wiring or connector fault
- Vacuum or intake leak
- Fuel or ignition problem
- Control module fault
3Can I drive?
Have it diagnosed promptly. If the car runs and drives normally, drive gently to a workshop. If it runs badly, stalls, overheats, loses oil pressure, or a warning light is flashing or red, stop safely and get professional help. If the code concerns the brakes, brake vacuum or brake assist, do not drive until it is checked: a hard pedal or longer stopping distance means stop.
This page gives general information. It is not professional advice. For a definite diagnosis and a repair quote, ask a qualified mechanic to inspect the car.
4Brand data 27
| Brand | Code | Description | System |
|---|---|---|---|
| BMW | P1721 | implausible signal or value Brand | Powertrain |
| BYD | P1721 | Gear 5/7 sensor 2 short circuit to 5V Brand | Powertrain |
| Chery | P1721 | Wheel Speed Signal: Rear Left (G46): Implausible Signal Brand | Powertrain |
| Daewoo | P1721 | Gear 1 Incorrect Ratio Brand | Powertrain |
| Daihatsu | P1721 | Engine torque signal abnormal Brand | Powertrain |
| DFFS | P1721 | Vehicle speed sensor circuit failure Brand | Powertrain |
| DFXK | P1721 | GNS signal implausible fault Brand | Powertrain |
| EOBD | P1721 | Gyorsaságjel Brand | Powertrain |
| Geely | P1721 | Wheel Speed Signal: Rear Left (G46): Implausible Signal Brand | Powertrain |
| GM | P1721 | Gear 1 Incorrect Ratio Brand | Powertrain |
| Great Wall | P1721 | GNS signal implausible fault Brand | Powertrain |
| Honda | P1721 | Park Pawl Unit IG1 SW No Signal Brand | Powertrain |
| Hyundai | P1721 | No description available | Powertrain |
| Isuzu | P1721 | No description available | Powertrain |
| Land Rover | P1721 | Gear 1 Incorrect Ratio Brand | Powertrain |
| Mahindra | P1721 | No description available | Powertrain |
| Maserati | P1721 | Intelligent Alternator Module Circuit Brand | Powertrain |
| Nissan | P1721 | No description available | Powertrain |
| Perodua | P1721 | Engine torque signal abnormal Brand | Powertrain |
| Peugeot | P1721 | No description available | Powertrain |
| Porsche | P1721 | Getriebeübersetzung 1.Gang in M-Gasse fehlerhaft Brand | Powertrain |
| Proton | P1721 | No description available | Powertrain |
| Saab | P1721 | Gear 1 Incorrect Ratio Brand | Powertrain |
| Subaru | P1721 | DCCD engine rpm signal system circuit Brand | Powertrain |
| Suzuki | P1721 | Neutral control circuit 1 malfunction Brand | Powertrain |
| Tata | P1721 | No description available | Powertrain |
| Toyota | P1721 | Gear 1 incorrect ratio Brand | Powertrain |
Legend: SAE is the generic J2012 description; Brand is text taken from that manufacturer’s data. Manufacturer rows keep the wording and language of the source data, and non-English text is tagged so screen readers pronounce it correctly.
5Extended variant codes 3
These 7-character codes are manufacturer-specific variants of P1721 and may be reported by some scan tools.
| Brand | Code | Description | System |
|---|---|---|---|
| Mercedes-Benz | P172100 | Fehlereintrag für Motorabwrgen wegen eines Fehlers im Stopp/Start-System Brand | Powertrain |
| Sprinter | P172100 | Fehlereintrag für Motorabwürgen wegen eines Fehlers im Stopp/Start-System Brand | Powertrain |
| SsangYong | P172100 | Throttle signal error Brand | Powertrain |
6Related codes
Browse Pxxx codes or P172xx codes.