Here's a good one. I got a fairly good deal on a '93 240 with a sunroof and have owned if for two weeks now. I've been looking it over and it's on very good condition. Someone even added daytime running lights, or so I thought. The lights seem to be on whenever they feel like. At first I thought some former owner had installed a photo cell to detect outside light for automatic headlights.

I finally figured it out. The other day I pulled into the driveway during the day and the headlights (and all the other outside lights) were on. I could see them reflecting off the garage door. Before killing the ignition, I happened to turn the radio off. The headlights went off. I turned the radio on, the headlights went on.

With the radio off the headlight switch works normally. With the radio on, the headlights, tail lights, etc. light and the switch has no effect. It's an aftermarket Sanyo radio that a former owner installed of had installed. They did a nice job and even the power antenna works fine.

Obviously someone somehow wired the radio power to the wrong side of the headlight relay. My questions are;

1. Has anyone ever heard of a goofup like this?
2. Has anyone ever heard of someone doing this deliberately?
3. Is there a way to download or otherwise get a clearer electrical wiring diagram than the Berkley manual has?

Thanks, so it goes,
Mark
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1993 Volvo 249 Sedan 114, 000+ miles. I love to drive it when my kids let me.

"...It's an aftermarket Sanyo radio that a former owner installed of had installed. They did a nice job and even the power antenna works fine...."
You should smack the owner who put that radio in...Then again, I can't talk; my '86 DL was worse-MUCH worse. I had bought the car with the intention of putting a sweet system in there, and I had already installed a CD player in my '84 244 so I figured this would be a walk in the park- WRONG. When I pulled the radio out, I alnost passed out-See the radio used to shut off when I put the directional on. So if I was to turn left, and use my blinker, well you could kiss the Rolling Stones goodbye. But as soon as I shut the blinker off, the damned radio would turn back on. So I figured that would be an easy fix, just a couple of wires to fix. Yeah no, not even close. The other owner had cut all of the wiring from the harness (the harness that is wired to the radio/cd player harness.) So I had to figure out what wires went to what. But for this, I wanted to get comfortable and the center dash console was in the way so I removed that to my horror: The previous owner had sprayed foaming insulation all over the wires behind the center dash console, and this foam ran all the way to the engine :-/. I knew then that I was driving this car on borrowed time, and sure enough, one day while trying to start the car up, smoke started billowing out from underneath the instrument cluster and center dash console. Then again this car was a 4 speed with overdrive, and fixing the overdrive was fun-3 hours worth of drilling out epoxy from the hole that the OD button ran through. Apparently the previous owner thought it was okay to epoxy the shift knob to the shifter. And what is even sadder is the previous owner is a firefighter- you figure he'd know something about spraying foam insulation on wires that get hot....

Following up on aleekat's note about alldata diy--it'll run you about $25 per year for the first car, and $15 or so for each additional car, for access to online shop manuals and wiring diagrams that look an awful lot like the green books, plus the dealer alerts and changes. the first wiring goof you don't make because you have the diagrams will probably save you a lot more than the 25 bux in either parts or time. I presently have 4 vehicles with subscriptions to alldata, and will continue as long as I own vehicles; I like being able to print out what I need for a job, make notes and grease spots on the hard copy, and know that there is a clean copy still in the computer. I have no other financial connection with them.
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We have met the enemy and they is us. [Pogo] S70 T5 cop car : Rough Rider suspension, Walmart fog lights, eBay speakers, ambiance by Pall Mall, trim by Le Duc d'Tape, 8-channel THD by OEM amps

Sounds like someone connected the wire for the light in the old radio to the ignition power. I want to say it's a brown wire, but I don't know for certain on a 93.

Pull the thing and have a look at what's spliced to what. Normally the radio side of the wiring harness, for aftermarket radios, use red and yellow for power supply, so have a look at what's connected to those wires. Separate them and see if one of the wires goes on and off with the headlight switch.

Good luck with it!
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Rob Bareiss, New London CT ::: 87 244DL- 249K, B230F/M47, Turbo sways, Bilsteins, GT braces, Virgos, Turbo exhaust, Gislaveds for winter!

re: "...It's an aftermarket Sanyo radio that a former owner installed of had installed. They did a nice job and even the power antenna works fine...."

Congrats on finding a '93 with a sunroof (it is factory, isn't it?) They're as rare as hens' teeth.

About your lights and radio, though. The installer probably did some hinky stuff to your wiring.
For point of reference, in a regular '93 (I have two of them, alas without sunroof ;-), the headlights are still controlled conventionally with the light switch while the engine is running, although once you've switched them on, the headlights go out automatically when you switch off the engine. And (assuming the light switch is still on), the headlights will turn on when you restart the car -- thus the headlights can serve as DRLs if you choose to leave the switch on. If you don't want them to work as DRLs, just manually turn the headlights off with the switch in the daytime. The parking lights, however, are totally conventional in their operation -- they're controlled solely by the light switch, regardless of whether the engine is on or off.
And of course, the radio works conventionally with the ignition key.

Compare the preceding to they way your car works, and it may give you a better idea of what's been changed as you examine a wiring schematic.

Good luck.

You can check with alldata.com for wiring schematic, but you have to pay.