The P1603 diagnostic code on a 2000 Volvo V70 represents a problem with the vehicle's electronic throttle module (ETM). When the accelerator pedal is used, it signals the engine control unit, which activates the ETM. Repairing this problem will preserve your engine speed control.
Symptoms of a P1603 diagnostic code on a 2000 Volvo V70 automobile include stalling and erratic revving. The engine warning light will also illuminate.
After 1999, Volvo V70 models had physical contact between two parts that control the throttle. This particular set-up was produced until 2002. Therefore, Volvo V70s manufactured from 1999 to 2002 suffered from wear, damage and failure of the two throttle parts that were in contact with each other. Approximately 500,000 Volvo gasoline cars were negatively affected by this design.
A Volvo Master Technician recommends a 155 software upgrade for this type of problem, and an ETM repair job takes between 2.5 to 3 hours. The dealer will replace the ETM under the vehicle's 10-year, 200,000-mile extended warranty.