howdy all -

The tail lights on my 88 240 do not work when the headlight switch is in the normal (2 o'clock) position. When I put the switch in the parking (12 o'clock) position they do work.

So far I have replaced the headlight switch to no effect.

From the diagram I have it looks like the next step would be to replace either the upper/lower beam switch relay or the bulb failure sensor. I haven't noticed any problems with either one...

Does anyone out there recommend I start with either? Or, am I missing something?

Thanks!

I've learned this past year to always check the fuses. While often it doens't seem like the problem, that's where I go first. Sometimes, for whatever reason, just wiggling them fixes all my problems.
I also had an issue with Rover (83 245) where the left hand tail light went haywire. I'd hit the brake, the turn signal would light. I'd put on my turn signal, the back up lights would blink. Turns out a chunk of metal the ground wire was bolted to rusted off the car. Simple fixes, but I was looking at relays and all sorts of things. Best of luck!

Sarah

bump... hope that's not bad etiquette around here, but I'm really stumped.

Well, let's see what the Volvo green wiring diagram book sez..

Tail lights power comes out of the BFWS relay. Red on the left, brown on the right. Front corner lights do not go through the BFWS relay - how are they working?

Power to the BFWS relay comes from fuse panel. #15 to left, white wire to the corner lights, the BFWS relay and to the license plate lights - how are they working?

#16 to right side, green to BFWS relay and front corner light.

Power to both fuses comes from the headlight switch. Terminal #58, white wire.

Somewhere along all those pathways must lie your problem. Check the easiest place first, of course. Fuses. Just looking isn't enough. Remove and put back. I've had them look dandy, and fall apart when touched.

Good Luck,

Bob

:>)

Thanks for the tips, Bob. Here's what I got so far.

-The front corner lights, tail lights, and license plate lights all work when the headlight switch is at 12:00 (parking lights) but do not when the headlight switch is at 2:00 (headlights).
-Fuses are tested and work.
-I did just replace the headlight switch, so unless both my old one and the new (IPD) one are broken, we can eliminate that.

Should the front corner lights work when headlights are on?

It seems like the BFWS isn't working properly when the headlight switch is at 2:00, but is working at 12:00, so I will begin testing around that. Thanks again for the help.

Alex

-The front corner lights, tail lights, and license plate lights all work when the headlight switch is at 12:00 (parking lights) but do not when the headlight switch is at 2:00 (headlights).

OK. So the front corners, tails, and license lights are NOT on when the headlights are on, right? (The front corners are ON when headlights are on.)


That's a good clue. Since only the tails go through the BFWS relay, and the others do not, I think the problem is not in that relay.

Lemme re-read the wiring diagram. Hmmm, new info here.

When the headlight switch is in parks-only position 12:00, power to the lights in question goes as the route I described in my first post.

HOWEVER, with the switch in headlight position 2:00, the route changes. Power to the fuses that feed the parks, tails and license lights flows NOT from terminal #58 on the headlight switch.

It flows to the fuses from the Headlight relay, terminal #87a. That relay is, IIRC, not found in another application on the 240s. It is a double-pole single throw relay, even though the prong configuration looks like a SPDT type.

It is a cube-looking relay, located usually above the driver's right toe. You will need to pull the felt sound pad, lie on your back and look up in there with a flashlight. I found that it is better for my eyes to do this after dark.
You may want to clean the carpet a bit, too.

Identify the relay by the colors of the wires going to the base. The terminal numbers cannot be seen, I will list them anyway.

Blue-white..#86...(hot from h-light switch) (shows yellow on some diagrams)
Black.......#85...(to a ground)
Green-red...#30...(to back of fuses #6-#10, hot from battery all the time)
White.......#87a..(to Fuses #15 and #16 for parks, tails, Lic lights)
Yellow......#87...(to step relay for headlights)

Before doing all that, I recommend that you hit a junk yard and pick up a relay or two. One should be good. Look at the prongs to check the terminal numbers, and check the condition of the base. If the base is good, get that, too. Clip wires with long-as-possible leads. Could be that your problem is the relay base (they overheat).


Hope this helps.

Goog luck,

Bob

:>)

Thanks for the very thorough rundown, Bob! I appreciate it. Will post with results once I track down a relay.

Alex

Keep bumping this until B.C. sees it and replies. Bob has owned an '88 and its wiring diagram manual and judging from his posts has committed every lighting circuit to memory. My foggy recollection is there are two different paths for the taillights/parking lights in those two positions due to the headlight relay at your feet, not the one under the hood.
--
Art Benstein near Baltimore