Troubleshooting / Fault codes
Engine coolant temperature sensor range/performance
P0116 is a cooling / thermostat / temperature sensor fault on the Mercedes Sprinter VS30 (OM642 3.0L V6 diesel). Mercedes describes it as: "Engine coolant temperature sensor range/performance".
What this code means
P0116 on the Mercedes Sprinter VS30 falls under the cooling / thermostat / temperature sensor fault group for the OM642 V6 diesel. The official Mercedes-Benz description is "Engine coolant temperature sensor range/performance". 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 P0116 Mercedes Sprinter fix or P0116 VS30 / OM642 information, start with a full scan to capture any related codes stored at the same time.
Official description
- Engine coolant temperature sensor range/performance
Symptoms
- Engine running cold or overheating
- Poor heater performance
- Check engine light
- Cooling fan running abnormally
- Reduced fuel economy when running cold
Warning — service soon
P0116 is a cooling / thermostat / temperature sensor fault on the Mercedes Sprinter VS30 (OM642 3.0L V6 diesel). Mercedes describes it as: "Engine coolant temperature sensor range/performance".
Possible causes
- Stuck-open or stuck-closed thermostat
- Faulty coolant temperature sensor
- Low coolant level or air in the system
- Wiring/connector fault to the sensor or thermostat heater
- Failing water pump (in some cases)
Diagnostic steps
- Scan and record all codes; read freeze-frame for coolant temperature.
- Compare the coolant temperature sensor's live reading to actual warm-up behavior.
- Check coolant level and condition; bleed air if needed.
- Test the thermostat operation (warm-up rate to operating temperature).
- Inspect wiring/connectors to the sensor and map-controlled thermostat.
- Replace the thermostat or sensor as indicated, then verify normal warm-up.
Recommended repairs
- Replace a stuck thermostat (open or closed) and bleed the system.
- Replace a faulty coolant-temperature sensor.
- Top up coolant and purge air from the cooling system.
- Repair wiring/connector faults to the sensor or map-controlled thermostat.
- Replace a failing water pump if circulation is poor.