So I've recently purchased some LED bulbs to replace my brake, indicator, and reverse lights on my 2003 S40. However I've ran into many problems.

When I installed the brake lights, both the "bulb out" and "DSA" indicator lights came up on the dashboard. When I installed the indicator lights, I ran into a hyperflashing issue that I thought could be solved by buying 3ohm 50W resistors to wire into the circuit. However this didn't fix the problem either. So now I'm stuck and I feel like I've wasted a lot of money on these bulbs. I'm wondering if anybody has successfully installed LED lights without any issues and what they had to do to make it work? Thanks

 

Also post your question over on Swedespeed Forums as there seems to be more modders active there.

 

Try removing the bulbs and refitting them again the opposite way round (180 degrees)
This is what you do with the LED's for the interior dash lighting.
Seems they are polarity sensitive but dont blow if put in the wrong way accidently.

 

I bought, meassured and found the after marker trailer adapters to make incandescent fail sensored cars work with LED lit trailers use 100 ohm resistors for the running and turn signal circuits. they go across the Led to make the circuit draw more current...not in series with the Led.

 

I also just tried to upgrade the brake light pair on my '01 S40 to LEDs and got the same issue with the "bulb out" and "DSA" indicator lights (why DSA would fail beats me). Once the incandescent bulbs were put back, all was well again. Asides from adding resistors, would anything else work? I have not tried reversing the bulbs yet...
Thanks!

 

If you can add the resistor and make a write up I bet many people would be appreciative. Seems LEDs are the future.

 

Any idea what resistance and where/how to connect it to the socket and/or bulb? I'm not really an electrical guru

 

Last week my uncle showed me a wiring diagram for the DSA system in the S40 and it revealed that the brake lights were somehow tied into the circuit for the DSA, which explains why that light comes on if the bulbs are out. Seems like a cheap shortcut that Volvo took. I wish I could find the diagram but unfortunately it was on one of those sites like alldatadiy and I don't have a subscription.

What I'm thinking about doing is buying some 1156 bulb sockets, like these 2XLED Bulb Socket Extension Replacement Holder Wire Harness 1156 1141 BA15S 7506 | eBay , and adding them into the circuit with the regular incandescent installed, then just tucking the bulbs out of sight somewhere. That way the power draw will be almost exactly the same and should (hopefully?) stop the hyperflashing issue. The only problem I can think of is the LED's not being as bright but only time will tell. I'll post an update as soon as I do it. I'm in the middle of doing a radio replacement job at the moment.

 

In terms of luminosity for the brake lights (asides from the burn-out and DSA issue) , these LEDs were just about the same as the stock incandescent bulbs... 2X 54 LED 1156 BA15S R5W 5630 SMD Auto Tail Turn Single Light Bulb DC 12V White | eBay

 

Read my ealier post above.....try a 100 ohm power resistor wired across the bulb and not in series with the bulb.

 

Try this link for the wiring diagrams you may be needing to assist you.
Comprehensive list of models included so just search thru for the S40. 2003.
Hope it helps you.
Volvo Wiring Diagrams

Wouldn't adding additional incandescent bulbs (however hidden) into the circuit along with the LED's result in very little gain as the incandescent bulbs will still require changing more frequently as per standard and overall the loads on the circuit would be higher than previous?
As soon as one of those bulbs blows the warning lights would also reappear.

 

I'm aware of this but I mainly care about how they look and plus I already have the bulbs so might as well put them to use somehow