Equipment repair, equipment failure, inferior goods, and urgent orders are major obstacles for scheduled production and contribute to low productivity and long lead-time in manufacturing plants with incomplete production technology. This paper presents a decentralized scheduling algorithm under the assumption that proper preventive repairs can decrease the occurrence of equipment failure and inferior goods. This algorithm can realize high productivity and short lead-time and be hardly affected by frequent equipment repair. The effectiveness of this algorithm is demonstrated by simulations of a plant model based on real plant manufacturing application specified integrated circuits.