OEM-quality Fog Lights on '10 Prius will not shut off

I bought the OEM-quality fog lights from the site's Prius store a while ago and had them installed. Two days ago, I was walking down my drive in the middle of the night to get the newspaper. My car was parked right outside the garage with the doors locked. I was startled to see that my fog lights were on....even though my car was off. My car had been sitting outside for 2 days due to a brief cold snap we had here (I had filled all 3 of the garage parking spots with thousands of my super-tropical plants so they wouldn't be hurt by the cold). Thinking back, this was the first time in a really long time that I have even seen my car in a nighttime/dark setting, so no telling how long my fog lights have been going without ever shutting off. I only drive my Prius about once every two or three weeks, so it usually is sitting in my garage. Anyway, I have turned it on/off, locked/unlocked it manually and with the remote, driven it up and down the street, turned the lights and the fog lights on/off in every possible combination, etc., and the fog lights simply will NOT go off. Nothing happens when I push the fog light button on the dash. When the car is powered off, the fog lights dim down to approximately the output of a 7w household nightlight. They brighten on up to their normal intensity/output once the car is powered on. I know NOTHING at all about car wiring, so I don't have a clue what might be wrong. Thankfully, I replaced the Prius battery with a more powerful one a while back; otherwise the car battery would definitely be dead by now. The dealership can't even look at my car until next week, so I would love to know if any of you might have any helpful ideas on why the fog lights will not shut off. Thanks for any input!

 

Hey, thanks for your reply. Yeah, it's gotta be that relay thing that you describe just not doing what it wants to do. They were installed to turn on and off with the car. I have always left the switch pushed on, and I have used the lights as driving lights. They've always shut off when I turned the car off....until now. So, whatever has "shut the power off" to them has just stopped doing its job correctly. So....next issue. The installer, that I have used for 20+ years, closed up shop in the middle of all the installation of my many electrical items that I added onto the car. Very little of my electrical stuff got wired up. The wires are all just tied up inside the engine bay. Anyhow, moral of the story, I no longer have an installer. I took my Prius to the Toyota dealership this morning and dropped it off. Is this "relay" thing a "universal thing" that the dealership would have access to and could repair/replace? Or, since I bought the fog lights from our Priuschat store, would I be have to somehow get a relay from the Priuschat store, or would I be stuck with having to trash the fog lights and buy all new ones (which I hope is not the case, as I sent them off previously and paid to have various LED lights installed in them --- which of course have yet to be wired up)?

I had hoped to post a response earlier, but I managed to get my very first computer virus last week, and I've spent every free second on the phone with Microsoft while they've been in my computer remotely, trying to completely remove it without having to do a complete reinstall. So, I'm actually sitting in the dealership lobby right now using their computer. lol! Anyway, I thank you all for your help with this and for taking your personal time to respond to me. I look forward to your responses and help!

 

Hey again. They've been installed over a year now. Well, of course, the dealership just called and said they've done everything imaginable, but that my fog lights shut off and turn on just like normal. Isn't that ALWAYS what happens when you take your car in? Now they say that they can't get the fog lights to stay on continuously like they've been staying on at my house for the past week. Of course, the lights were still on when I got out of my car at the dealership. I checked that right away, just in case my car decided to pull a fast one and "act right" for the mechanics. Just like always happens, they drove my car around to their mechanic's bay to be checked out and the fog lights suddenly worked just perfectly. But you know they'll stay on continuously again the minute I get my car back to the house... How frustrating! I asked the dealership how much "the relay" cost, in case you guys said that my relay would be the same practically as a Toyota one (waaaay above my head!). They said $106. They said that the only relay they could see, though, would be the relay that somehow connects to/with the headlight switch...I think. I personally can't see how the fog light relay would have anything to do with any relay that is associated with the headlights. However, I'm trying to imagine all this in my mind, and I understand none of it... I did suddenly remember some other fog light "behavior" last week that was weird. One time when I got out of my car, during my many attempts last week to get the fog lights to shut off, the fog lights flickered up and down between bright and dim really fast for about 5 -10 seconds after I shut off the car, kinda like a fluorescent light will do that is in the process of dying. I don't think I had recalled that fact in my previous posts here. It just came to me earlier. Anyway, is that how a relay would behave that is going bad? Also, this "relay" that we are referring to, is it something that came with the fog light kit? If so, this relay could be installed anywhere in the car? I know that the installer ran the wires thru the firewall. So, the relay would be....inside the dash, back behind the fog light on/off switch? or somewhere in the engine bay, never to be found again? Thanks!