Troubleshooting / Fault codes
Output speed sensor circuit
P0720 is a transmission / drivetrain fault on the Mercedes Sprinter VS30 (OM642 3.0L V6 diesel). Mercedes describes it as: "Output speed sensor circuit".
What this code means
P0720 on the Mercedes Sprinter VS30 falls under the transmission / drivetrain fault group for the OM642 V6 diesel. The official Mercedes-Benz description is "Output speed sensor circuit". The ECU sets this code when it detects an out-of-range condition in this system. Use the symptoms, common causes, and diagnostic steps below as a starting point, and always read the live data and freeze-frame for this specific code before replacing parts. If you're searching for the P0720 Mercedes Sprinter fix or P0720 VS30 / OM642 information, start with a full scan to capture any related codes stored at the same time.
Official description
- Output speed sensor circuit
Symptoms
- Harsh, delayed, or erratic shifting
- Slipping or flaring between gears
- Limp mode / stuck in one gear
- Check engine light (often with P0700)
- Transmission running hot
Warning — service soon
P0720 is a transmission / drivetrain fault on the Mercedes Sprinter VS30 (OM642 3.0L V6 diesel). Mercedes describes it as: "Output speed sensor circuit".
Possible causes
- Low or degraded transmission fluid
- Failing shift solenoid or valve-body fault
- Faulty speed sensor
- Conductor plate / internal wiring fault
- Torque converter clutch wear
Diagnostic steps
- Scan all modules; read TCM companion codes (P0700 is only a flag).
- Check transmission fluid level and condition.
- Read live data: gear, speed sensors, and shift/lockup status vs. command.
- Service the fluid and filter if degraded.
- Test solenoids and the valve body.
- Repair the underlying fault, then road-test through all gears.
Recommended repairs
- Service the transmission fluid and filter if degraded.
- Replace a failing shift solenoid or repair the valve body.
- Replace a faulty speed sensor.
- Replace the conductor plate if internally faulty.
- Rebuild or replace the torque converter if the lockup clutch is worn.