Headlight Switch Module Not Working, DIM is dark, and radio is dark. Why? Help! Topic is solved

JohnnyBee323 · Post by **JohnnyBee323** » 13 Mar 2018, 13:14

Hi all,

I am new to this forum. I recently purchased a 2004 Volvo S60 2.5T FWD from a friend. One morning I stopped at the gas station, and when I went to turn on the car the Driver Information Module on the dash had gone dark (barely readable), the radio display had gone dark, and I more recently noticed the headlight switch module is not working.

Can someone please help me understand how I could fix this? Is it is as simple as a replacing the headlight switch module?

Please note, the DIM seems to still be working, its just very very dim. My high beams and low beams still work just fine, and the radio works too although I can't see which station its on. I did notice that when I hit the fuel latch unlock button on the headlight switch module, notifies me on the dim (from what I can see). This leads me to believe that the source of the problem is with the headlight switch module, and it might just need replacement.

Thank you in advance for the help!

Post by **ljsommar** » 13 Mar 2018, 20:41

I was experiencing very similar if not identical symptoms and replacing the headlight assembly with a used one off ebay did resolve things. Very easy to replace 5 minutes or less.
Good luck

Post by **oragex** » 14 Mar 2018, 08:03

I think the above comment means replacing the switch module? Mine also makes truoubles. Not sure how easy to replace as it sits quite firmly in place.

Post by **ljsommar** » 14 Mar 2018, 11:54

Yes, I meant the switch module. Sorry for the mistake. To replace: open the door, pop the fuse panel access cover, push out the switch module, disconnect the connector. Doesn't get much easier.

Daveliz99 · Post by **Daveliz99** » 20 Mar 2018, 17:30

I have the same problem on my 2001 V70 2.4T.

I looked through the junkyard the other day but the only ones they had have the gas tank button on the left. On my car, that button isn't there. It just has the fog light button and where the gas door button is, it's just blank.

Will it still work?

Post by **abscate** » 20 Mar 2018, 22:47

Does your gas flap lock? Maybe it’s integrated into central Locking? If that’s so, the module should work with the extra button just bring dormant

Post by **mrbrian200** » 20 Mar 2018, 23:30

The gas flap locks automatically when you put the car in drive and reach a certain speed around 3 or 5 mph. If you unlock the flap, then lock the doors, the flap automatically relocks after a timer. Don't know how long the timer is but it's more than 5 minutes. The REM controls the flap locking mechanism motor by reversing polarity DC through 2 wires. The button on the light switch module communicates to tell the REM to unlock the flap via CAN data. The REM is responsible for relocking it (software).

The dimmer functions are controlled by CANBUS data generated at the light switch module based on the position of the thumb wheel. As other functions of the LSM are still working it's probably the analog pot on the thumb wheel that failed. But note: all dimmed lights are controlled via CAN data. The LSM is not hardwired to power any of these instrumentation lamps directly. I explain this so that you understand that there is not a wire you can simply bypass the LSM to connect +12v to light up these instrumentation lamps. You have to replace the light switch module.

The light switch module is considered plug and play: if it has the same buttons in the same places as the one on your car it should work, in your case it must come from a S60 2001-2009 or a V70 2001-2007.

Post by **abscate** » 21 Mar 2018, 04:06

Volvo parts lisle shows that the lower two buttons pop out so a junkyard or PnP part should adapt

http://volvopartslisle.com/part/OEM-Vol ... ght-Switch

Post by **mrbrian200** » 21 Mar 2018, 09:39

abscate wrote: ↑21 Mar 2018, 04:06 Volvo parts lisle shows that the lower two buttons pop out so a junkyard or PnP part should adapt

http://volvopartslisle.com/part/OEM-Vol ... ght-Switch

That makes life easy. Pull any S60/V70 LSM from salvage, switch the lower buttons if they're not the same.

Daveliz99 · Post by **Daveliz99** » 21 Mar 2018, 10:23

Yes that does make life easy. I'll try it asap.

Just to clarify, my thumbwheel nor any other part of my lsm works. Most of my dash lights went dim, radio display out, bright headlights won't stay on etc. Other people who posted similar symptoms said they had some success by changing the lsm.

Thank you both for the help.