P0720 on Hyundai
Output Speed Sensor Circuit Malfunction
P0720 on Hyundai vehicles indicates output speed sensor circuit malfunction. Au7o has documented this code across 1 Hyundai model — most commonly on Elantra. P0720 indicates a malfunction in the transmission output speed sensor circuit. The output speed sensor measures how fast the transmission's output shaft is turning, which the computer uses to calculate vehicle speed, control shift timing, and manage torque converter lockup. When the signal is missing or implausible, the transmission may shift harshly, get stuck in one gear (limp mode), or the speedometer may read incorrectly. The fault is usually in the sensor, its wiring, or the connector, though internal transmission issues can also be responsible. Typical repair costs on Hyundai range from $150 to $450, depending on the specific model and root cause.
Common Causes of P0720
- •Failed output (vehicle) speed sensor
- •Damaged wiring, connector, or corrosion in the sensor circuit
- •Metal debris on the sensor tip or damaged reluctor ring
- •Open or short in the signal circuit
- •Low or contaminated transmission fluid affecting components
- •Poor ground or reference voltage to the sensor
- •Faulty transmission control module (TCM/PCM)
P0720 on Hyundai by Model
Hyundai Elantra(1 issue)
- Automatic Transmission Input/Output Speed Sensor Failure Causing Harsh Shifting2001-2006
Owners of automatic-transmission Elantras from this generation frequently report sudden harsh shifts, incorrect gear selection, limp mode, or a stuck speedometer caused by failing transmission speed sensors. Hyundai service literature and repair databases commonly reference input and output speed sensor faults on these vehicles. The problem often appears intermittently at first, then becomes more consistent as the sensor signal drops out.
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What does P0720 mean on Hyundai?▼
P0720 stands for "Output Speed Sensor Circuit Malfunction." P0720 indicates a malfunction in the transmission output speed sensor circuit. The output speed sensor measures how fast the transmission's output shaft is turning, which the computer uses to calculate vehicle speed, control shift timing, and manage torque converter lockup. When the signal is missing or implausible, the transmission may shift harshly, get stuck in one gear (limp mode), or the speedometer may read incorrectly. The fault is usually in the sensor, its wiring, or the connector, though internal transmission issues can also be responsible. On Hyundai specifically, this code is documented across 1 model.
What causes P0720 on Hyundai vehicles?▼
Common causes on Hyundai: Failed output (vehicle) speed sensor, Damaged wiring, connector, or corrosion in the sensor circuit, Metal debris on the sensor tip or damaged reluctor ring, Open or short in the signal circuit, Low or contaminated transmission fluid affecting components. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0720 on a Hyundai?▼
Repair costs on Hyundai range from $150 to $450, depending on the specific model and root cause.
Which Hyundai models have P0720 documented?▼
Au7o has documented P0720 on 1 Hyundai model: Elantra.