P0720 - Output Speed Sensor Circuit Malfunction

P0720 is a transmission control, speed sensor, gear ratio, solenoid, or torque converter clutch fault. Pull transmission-module data and prove fluid, circuit, command, and mechanical condition before quoting major repair.

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Common Next Steps

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Code Overview

P0720 is a transmission control, speed sensor, gear ratio, solenoid, or torque converter clutch fault. Pull transmission-module data and prove fluid, circuit, command, and mechanical condition before quoting major repair.

Common Causes

• Low, burnt, contaminated, or incorrect transmission fluid
• Input or output speed sensor signal fault, connector issue, or wiring damage
• Torque converter clutch solenoid, shift solenoid, pressure control, or valve body problem
• Internal clutch slip, worn converter, hydraulic leak, or mechanical transmission wear
• TCM/PCM communication or power/ground issue
• Engine performance problem causing shift complaints before a transmission repair is needed

Symptoms

• Check engine light or transmission warning
• Harsh shifts
• No overdrive or limp mode
• Torque converter shudder
• Poor acceleration
• Speedometer or shift timing issues

Diagnostic Steps

1. Scan the transmission module for manufacturer-specific codes because P0700 is only a request code
2. Check fluid level, condition, smell, metal debris, leaks, and correct service procedure
3. Compare input speed, output speed, gear command, slip RPM, TCC command, and line pressure data
4. Inspect transmission connectors, harness routing, grounds, and power supply before replacing solenoids
5. Road test while logging shift timing, slip, TCC apply, temperature, and failsafe events
6. Confirm repair with a warm road test, no pending transmission codes, and normal shift/TCC behavior

Repair Difficulty

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Likely Repairs & Cost Guides

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Related OBD Codes

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Next Steps

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