One problem related to engine engine control module (ecu/ecm) has been reported for the 2004 Toyota Sienna. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Toyota Sienna based on all problems reported for the 2004 Sienna.
The contact's mother owns a 2004 Toyota Sienna. While the contact's mother was driving at an undisclosed speed, several unknown warning lights illuminated. The contact stated that the warning lights illuminated on and off for days and months. The vehicle was taken to an independent mechanic where dtc: p2241 was retrieved. The vehicle was not repaired. The contact was advised to take the vehicle to the dealer. The vehicle was taken to the dealer where the failure code was confirmed. The contact was informed that the oxygen sensors needed to be replaced. In addition, the contact was informed that a TSB for the ecm software update needed to be performed. The contact stated that the vehicle was not repaired because the ecm software update was performed, and the ecm software update damaged the ecm. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 150,132.