The use of Information Systems in Fault Diagnosis CHRIS DAVIES and RICHARD GREENOUGH School of Industrial and Manufacturing Science, Cranfield University, Cranfield, Bedford MK43 0AL E-mail: chris.davies@cranfield.ac.uk Abstract Excessive downtime remains a problem for many organisations, particularly those using complex capital intensive manufacturing processes. To counter this, many use computerised management systems to support various aspects of their maintenance activities including breakdown diagnosis. This paper describes research that has been undertaken to investigate the effectiveness of maintenance information systems to support activities during machine breakdown. A survey has been conducted to investigate computerised management system applications from the user perspective. The survey was designed to solicit user opinion on effective maintenance user support and the usefulness of existing IT systems to various personnel. The combined survey results and literature review are used to inform the development of a pilot maintenance information system that will be evaluated in a future study. 1. Introduction Research has been undertaken to ascertain current attitudes toward the use, implementation and effectiveness of computerised maintenance information systems. A survey was used to research current user opinion on the usefulness of existing IT systems within a maintenance environment. Other information sought, was the level of system accessibility to differing personnel, information availability, and the level of user contribution to such systems. 2. Literature review, Information Support Systems Background Computerised information support systems use different techniques and approaches to satisfy different maintenance requirements. Expert systems (ES) are rule- based systems developed to support specific tasks with known outcomes [6]. Computerised maintenance management systems (CMMS) assist in planning, management, and administrative procedures for effective maintenance [1]. Enterprise resource planning (ERP), is the integration of a single company wide information support system, serving the particular needs of different areas within the company [12]. The use of interactive electronic technical manuals (IETM) provides information support through the use of technical documentation presented as digital information [11]. Developed as referential technical manuals, digital maintenance manuals use