Hi Bill. Based on your recommendation I've now ordered a pair of Auxito 1157 red LEDs to try. The specs for lumens are definitely good compared to others in the same price range. These are made in China and the eBay link you provided was a Kentucky seller with over 3 week delivery. You said the price was $12 a pair, but they're now $14 plus $11 shipping plus whatever tax applies, so more like $12 per bulb. You can currently get them directly from Auxito in China on their Aliexpress store for less than half that, $10 pair, w/free shipping, tax/brokerage/duty exempt, same 2-3 week delivery, so likely where the eBay seller is getting them. These aren't going to be knockoff Auxitos, you're just eliminating all the middle men, warehousing and standard shipping costs. I've ordered lots of half-decent stuff like this from Aliexpress over the years without any major problems other than the sometimes long shipping times. You can get an instant refund if the item doesn't arrive in time, is DOA, is not as advertised, or is found to be a knockoff.

BTW, you're quite right, it's not always intuitive, but you use red LED's behind a red lens so that none of the rated lumens are filtered out by the lens, whereas a bright white is fuller spectrum with only some of the lumens in the filtered red wavelengths. If you do further reading, real world experiments show that using a yellow LED behind an amber lens may not be as bright as using a white light of the same lumens behind an amber lens. The explanation is that the shade of amber lenses varies greatly from light yellow amber to reddish orange amber. The yellow LED wavelengths are in a relatively narrow band and these often don't fully match the amber wavelengths being allowed through the plastic lens.

Although a bit off topic here, since you and Kitty mentioned it in another thread I'll tell you how I easily shared the rear fog lights with the brake lights in my 740 using diodes and just as easily done with 240s. The way to do it is make a "Y" with two suitably wattaged diodes making a common output. You do it up behind the fog light switch. Sever the output of the fog light switch, with the wire from the switch to one arm of the Y and the wire to the foglights on the tail of the Y. The other arm of the Y is connected to the brake light switch. Power from either switch goes to the fog lights, but won't back feed into the other circuit, so you can have the best of both worlds using the fog light switch. This is ahead of the bulb out sensor so won't create problems. When you sever the wire, if you install a male/female bullet or spade junction at the cut wire then you can quickly go back to the original if a diode fails or you decide you don't like it. I crimped matching bullets directly onto the diode and then heat shrinked the whole thing.

The problem doing this with the newer 700/900s and many of the replacement taillight assemblies is that they now only have a single rear fog light, with DOT following the long time European standard. It's done for safety reasons so when someone flicks the fogs on, a closely following may go into panic mode thinking you're jamming on the brakes, which can lead to an accident. The opposite taillight assembly now normally has a mould with the hole filled in and no bulb contact strips. The plastic blank can easily be Dremeled out to accept a bulb holder, which you will need to procure. Different left and right bulb holders were used so you need to doublecheck which fits the now exposed moulded tabs. You can then solder wires to the bulb holder terminals.

I will caution that using standard single filament 1056 bulbs in the fogs along with the double filament 1157s in the brakes can make for a very large and bright double brakelight, almost too bright for following cars at night. I had a couple of complaints from friends who often followed me driving to/from work. Stopped behind me at a light their faces were very lit up at night in my mirror. The diodes I had on hand and used in my 740 mod were perhaps a bit under-rated and blew within a year, so I yanked the Y out, reconnected the bullets and never got around to fixing it before selling the car.

If I had nothing better to do then I would make the same mod to my 940 wagon taillights, but I'd rather just go for brighter LEDs rather than doing taillight surgery. The first two cheapo brands of LED 1157 equivalents I got as an experiment were barely as bright as the originals and the viewing angles were poor, so I took them back out.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

Hi Dick,

Here's a good link:

https://volvo240-260.com/?dir=Wiring%20diagrams

Get the Charging manual TP30729-1
Also find the complete wiring manuals for 1985 and 1993
They are big files.

There's also a series of smaller Mitchell's schematics for each year
including your 1988. They are not in the same league with the Volvo
fault tracing, component ID and location etc.

Try to find the 1988 book, your best troubleshooting pal for your car.

Bill

Awesome, thanks Bill on the bulb recommendation! I'll look into them & report back.

Yes,I'm getting the readings with the engine running. And yes the results are a problem. But with 35 y/o wiring, it just seems more reasonable to accommodate a lesser load on the wiring & remedy it from there, if there's another cause due to some other electrical issue; hopefully AAA can tow me home.

Happy holidays!



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'88 245,M47,Virgos,270K(300k realistically)