Vehicle Application:

2002 Golf GTI 1.8L and Jetta GLS Wagon 1.8L;

2003 Beetle 1.8L and 2.0L; Jetta GLS Wagon 1.8L and GLS 2.0L; and Passat 1.8L;

2004 Beetle 1.8L and 2.0L; Jetta 2.0L and GLS 2.0L;

2005 Beetle 2.0L; and

2006 Passat 2.0T 2.0L

Customer Concern:

Check Engine light is on. Trouble code: P2181 (18613).

Potential Causes:

– Connector

– Defective Coolant Temperature Sensor (CTS) Wiring

– Defective Thermostat

Tests/Procedures:

1. Measure engine temperature and ensure it is getting up to proper operating temperature.

2. Connect a Volkswagen-compatible scan tool and monitor engine temperature on the scan tool. Compare to the actual engine temperature to determine if the coolant sensor is working correctly.

Tech Tips:

Code P2181 (18613) is for cooling system performance. It generally means that the vehicle has a defective or leaking thermostat. If the vehicle does not warm up quickly enough to go into closed loop operation within the time programmed into the engine control module, it will set this code. This is generally cured by replacing the thermostat.

Courtesy of Identifix, Inc.