Hi KaiS,

See:
http://www.volvowiringdiagrams.com/

There may be green manuals with this information someplace. You may want to see the section on 1997-1998 Relays.

Also at Dave Barton:
http://www.240turbo.com/volvorelays.html

The relay location info is helpful if you have a failed relay, or a relay set into a socket on the primary 700-900 relay board or elsewhere. As corrosion can form between the relay termination pins and the socket slots that hold in place the termination spade at the end of the wire harness conductor.

See DeoxIT D, a dielectric treatment that can dissolve corrosion that inhibits current flow. Also, a wiggle or remove and replace of the relay from and back into the socket can help, yet if corrosion is advanced, where heat is persistent, the terminal spade at the end of the wire harness on the underside of the relay platform (or the earlier relay / fuse platform).

The same is true of the headlight bulb to socket connection. Bulb heat into the bulb wire harness socket connector can form corrosion. A wiggle or replace.

Also, do you have any unwanted moisture intrusion into the headlight reflector chamber? I'm unsure what year, and I'll guess you have glass headlight lenses, yet the grey adhesive Volvo used to seal the plastic (as with 1986+ 240, most of the 700-series series production run, and early 900) or glass (later 900 series) can loose adhesion and seal as it ages with exposure and headlight temperatures. You should not, or very rarely at worst, ever see moisture condensate inside the headlight lens.

It helps if you describe the symptoms / indications of the failure. So that others can help you in subsequent replies.

How many miles?

Questions?

Hope that helps.

MacDuffed.
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