Diagnostic Trouble Code.
P0720 Repair Cost: Output Speed Sensor Circuit Malfunction
Real mechanic repair costs, DIY parts pricing, symptoms, and step-by-step diagnostic procedures for trouble code P0720.
Driveability Risk: Caution
Severity: HighSafe for short emergency drive. Automatic transmission will not upshift correctly.
Verified Replacement Parts & Diagnostic Sockets
Primary Replacement Part
Transmission Output Speed Sensor (OSS)
Direct OEM fit component designed to clear trouble code P0720 and restore factory engine performance.
Diagnostic Tool
Autel AutoLink AL319 OBD2 Scanner
Reads live freeze frame sensor data, resets code P0720, and verifies internal emissions readiness monitors.
Cleaner & Chemical
CRC Precision Sensor & Intake Cleaner
Removes carbon buildup and oil residue from delicate sensor pins without damaging internal plastic housings.
SelectMyBlog earns a small commission on qualifying purchases made through Amazon links. We recommend parts built to strict automotive tolerances.
Code P0720 Repair Cost Calculator
Adjust your local mechanic hourly rate to estimate total repair shop bills versus DIY savings for code P0720.
Standard Book Time: 0.8 - 1.8 hours
DIY Parts Only
$30 - $95
Hardware OnlyProfessional Labor
$100 - $225
Shop Labor ChargeTotal Shop Bill
$130 - $320
Parts + Labor TotalDIY Savings
$100 - $225
Kept in Your WalletSymptoms of Trouble Code P0720
When code P0720 logs in computer memory, it triggers distinct drivability symptoms and dashboard warnings. Inspect these common indicators to confirm the fault before buying parts.
- Harsh transmission shifts: The engine control unit detects out-of-range sensor feedback during regular drive cycles.
- Transmission stuck in single gear: The engine control unit detects out-of-range sensor feedback during regular drive cycles.
- Speedometer error: The engine control unit detects out-of-range sensor feedback during regular drive cycles.
Most Common Causes for P0720
Automotive diagnostic data isolates the most probable mechanical and electrical failures behind code P0720. Check high-probability items first to avoid swapping good components.
Failed Output Speed Sensor on Transmission
65%
Wiring Harness Rubbing Against Driveshaft
25%
Dirty Transmission Fluid Metal Shavings
10%
How to Diagnose Code P0720 Like a Professional Mechanic
Follow these four steps to find the fault behind code P0720. Test circuits and sensor wires before buying new parts.
Step 1: Scan Freeze Frame Data and Clear History
Plug a scan tool into the port under the dash. Record freeze frame data like coolant heat, engine RPM, and road speed. Clear the code. Take a ten-minute test drive. See if code P0720 resets right away or only under load.
Step 2: Inspect Wiring Plugs and Cable Terminals
Inspect the wire bundle at the Transmission Output Speed Sensor (OSS). Check the plug for broken tabs, loose pins, or green corrosion. Road grime leaks past old seals and grounds low-voltage lines. Spray pins with electrical cleaner.
Step 3: Measure Sensor Reference Voltage and Ground
Turn the key on with the engine off. Use a multimeter to check voltage on the signal wire. Modern sensors need a clean five-volt feed from the computer. Test the ground wire for continuity with under 0.2 ohms resistance.
Step 4: Verify Mechanical Tolerances and Component Health
If wires test good, check the physical part. Remove the Transmission Output Speed Sensor (OSS). Inspect it for cracks, carbon soot, or binding. Check your vehicle specs in our fuel cost calculator before wrapping up.
Essential Repair Hardware for Code P0720
Exact Vehicle Match
OEM Replacement Transmission Output Speed Sensor (OSS)
Direct factory fit. Matches original equipment electrical calibration and mechanical mounting points.
Hand Tool
GearWrench Automotive Mechanics Tool Set
Features low-profile ratchets and deep metric sockets to unbolt tight engine bay hardware without rounded corners.
Circuit Tester
Astro AI Automotive Digital Multimeter
Tests sensor reference voltages, circuit continuity, and ground paths with high automotive precision.
SelectMyBlog independently evaluates automotive testing gear. Quality tools allow home mechanics to diagnose faults accurately.
Common Vehicle Models Affected by P0720
While code P0720 follows standardized SAE OBD2 diagnostic protocols, specific vehicle manufacturers experience unique failure patterns due to engine layout and sensor placement.
| Vehicle Platform | Typical Failure Point | DIY Part Price | Average Shop Cost |
|---|---|---|---|
| Ford / Lincoln (F-150, Explorer) | Wiring rubbing against metal bracket or aging sensor probe | $30 - $95 | $134 - $329 |
| Chevrolet / GMC (Silverado, Tahoe) | Sensor element carbon buildup or internal circuit breakdown | $30 - $95 | $130 - $320 |
| Toyota / Lexus (Camry, RAV4, Tacoma) | Loose vacuum fitting or degraded electrical terminal contact | $30 - $95 | $126 - $311 |
| Honda / Acura (Civic, Accord, CR-V) | Intake boot tear or sticking solenoid valve seat | $30 - $95 | $126 - $311 |
Frequently Asked Questions About Code P0720
Can I drive safely with trouble code P0720 active?
Safe for short emergency drive. Automatic transmission will not upshift correctly. Driving status is rated as Caution. Primary symptoms include harsh transmission shifts and transmission stuck in single gear. Trips under 30 miles remain manageable, but arrange repairs promptly to protect secondary engine components.
How much does a repair shop charge to fix code P0720?
Repair shop bills to fix trouble code P0720 (Output Speed Sensor Circuit Malfunction) typically total $130 to $320. Professional mechanics charge for 0.8 to 1.8 hours of book labor ($100 to $225 at standard shop rates), plus $30 to $95 for a replacement Transmission Output Speed Sensor (OSS). Performing the work at home eliminates shop labor charges.
What is the most common cause of code P0720?
The primary cause of P0720 (Output Speed Sensor Circuit Malfunction) is failed output speed sensor on transmission, responsible for 65% of verified service repairs. The second most common cause is wiring harness rubbing against driveshaft at 25%. Test the Transmission Output Speed Sensor (OSS) and inspect connector terminals before buying replacement parts.
Will my vehicle pass an emissions smog check with code P0720?
In jurisdictions with automated OBD2 inspection checks, an illuminated Check Engine Light for code P0720 causes an immediate inspection failure. Although P0720 targets transmission or speed systems, the computer logs an active DTC that blocks state inspection clearance. Inspect the Transmission Output Speed Sensor (OSS) and clear computer memory before testing.
Will code P0720 reset itself after installing a new Transmission Output Speed Sensor (OSS)?
The computer clears code P0720 automatically once it completes two to three consecutive drive cycles of 50 to 100 miles without detecting harsh transmission shifts or circuit voltage irregularities. You can also clear the code immediately using a handheld OBD2 scanner tool after finishing the repair.
Can a weak car battery or charging issue trigger false P0720 codes?
Yes. Automotive control modules require a steady 12.4 to 12.6 volts to process sensor reference signals accurately. When a dying battery drops below 10.5 volts during cold cranking, the computer often registers false P0720 faults. Test resting battery voltage and alternator output in our car battery size guide before replacing the Transmission Output Speed Sensor (OSS).
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