DTC 1-4-5 - Fuel Injector Problem
WARNING: This page is about a different car, the 1996 Volvo 850. However, it is still accessible from the selected car via links, so may be relevant.
See DTC 1-1-5, 1-2-5, 1-3-5, 1-4-5 & 1-5-5 - FUEL INJECTOR PROBLEM circuit test.