I have a 1999 Volvo S80. Saw the same vehicle at pull a part that was fully loaded so I got the front fog lights, switch, relay and fuse. Put them all in and grabbed my laptop with VIDA and DICE (2013A) and proceeded to turn them on but no luck. I've used VIDA to turn off the DRL so I figured I could turn on the fogs. Here's what I did:
Vehicle communication -> CEM -> Activations -> Front fog light relay
When I click on that, off to the right it shows:
Front fog light relay
Possible activations
Activated
Below that it says
Front fog light relay - not activated
However if I click Start, I hear the click and the fog lights come on and it changes to activated but as soon as I exit out of the screen, it shuts them off and goes back to not activated.
Am I overlooking something or is this a trip to the dealer?

 

The activations in VIDA are just commanding various things on or off, not changing the programming of the car. I'd have to double check, but I am fairly sure you need a software download to enable fog lights.

 

Thanks ES6T. I was thinking I could download the software thru VIDA but from what I'm reading, I need a user name and password. Guess I'll look for an indy shop before driving 40 miles to the dealer.

 

Wow, software to activate fogs. SMH

 

Yeah you need a legal subscription to VIDA to do software.

 

Called around to a few indy shops. None can do it. One shop told me they used to be able to until Volvo started charging them about 10 grand to have the license. Said it wasn't cost effective. Don't blame him. Called the dealer, got put on hold for 10 minutes then got voicemail. Left a message & haven't got a call back. Been 2 hours. Guess they don't want to make a quick buck. I'm assuming they'll only charge $50 as that's what Land Rover charged me to re-flash my ABS & immobilizer.

 

It'll be more than $50. The software alone is probably around that price.

 

Just heard from back from dealer. It may not be able to be programmed. It's over 10 years old and they can't bring up the info for my car. I would have to come in and pay them $90 +tax just to see if it can be programmed then if it can, it's another $64 +tax for the software. I don't know if it's worth almost $200 to turn on fog lights. A toggle switch seems like a cheaper alternative.

 

There is a fog light application software for the 99 S80, so yes, it can be done. But with labor usually being an hour for a download, you'll be at around $200.

 

Well using VIDA, I was able to determine the "trigger" on the relay to turn on the fog lights. It's the top left post on the relay which is a ground. Odd that a ground activates the fog lights. So my plan is to use the old headlight switch and remove the front fog switch cover and install a slider on/off switch. I'll run the wire from the relay to the switch and the other wire from switch to ground. I'll play with this tomorrow with an in-line fuse of course, in case it doesn't work.... I don't want to burn it to the ground.

 

Ground side switching is the norm. Without the software, I'm not sure if the relay has power so you might want to double check that too.

 

There is power to the relay. Problem is there's always power to the relay so I just have to make sure I don't leave them on. Installed switch and seems to work well. Not pretty, but practical and I'm not out $200.

 

Probably way too late for cosmetics here........BUT would it not have been better to swap the reverse fog light switch to the blank cover. I figure I will never have the need for my single reverse fog light.