The following Wiring Diagram applies for Volvo S40 and V40 2004 models. Herein you will find detail information about the electrical specification, features, maintenance, and service procedures. Every component has a component designation consists of two parts. The first part is a type number that describes the type of component in question, for example 3/xx. The second part of the designation is a serial number, for example, x/2.
This wiring diagram manual is divided into sections which cover discussion on electrical distribution, fuses, relays, distribution rails, ground connection, control modules, electrical cooling fan, charging circuit, etc.
Find more information about the Volvo Wiring Diagram S40/V40 2004 here (pass: wiringdiagrams21.com)