Last monday I picked up my girlfriend and i noticed a little bit of water on the floor, but had no idea where it came from. At the time of me noticing, it wasn’t raining so I was really confused. Fast forward a few hours later, she noticed water was leaking in from the passenger side. I didn’t know what it was at the time, so i asked around and found out the drain was plugged with debris. I ended up removing the debris, clearing the drain. A day later I started experiencing electrical problems. For instance, the interior lights on the roof of the car would stay on and not go off. I ended up looking in the manual, pulling the fuse out and also disconnecting the lights. I also noticed that a little bit of water was in the SBJ, but not enough to ruin stuff in my car.

3 days later *Friday,* I left for work and the lights on the climate control turned off, my radio kept turning off, completely and coming back on. After a long day at work, i got in my car and when i went to start it, the right turning signal was on. I thought I flicked it up earlier that morning before i went into work, but that wasn’t the case. The turning signal, to this day is on. It won’t go off.

Yesterday I noticed that the lights are working again, my radio is back on, so I drove the car and for about 30 secs, the signal went off, then it came back on. Ever since then, it would not go off. I don’t know what to do. Please help… I need to drive my car, but how could i do that with a blinking light!!!

 

2009 Mustang GT

 

The smart junction box got wet enough to cause those issues. Since you saw water coming in, all those symptoms say the SJB is bad.

 

Ahh okay. thank you!! i was going nuts trying to figure out if it was or not.. i guess i’ll order a used one.

 

Try cleaning all the contacts and applying dielectric grease first. This might just save you a bunch of $$$.

 

my issue has been resolved. instead of spending any money at all, i went out with a hair dryer, unplugged each fuse 1 by 1 and hit it with heat until all was dry. I left the car til morning, and the light went off! IF it does come back on, I know what to try next.

 

You are only delaying the inevitable if you don’t take further action. In all probability the rubber drains below the windshield have become plugged. They need to be cleaned out or removed. While you’re at it, you probably need to replace the cabin incoming air filter since the rainwater had to come thru the filter opening to get inside. You should remove the smart junction box in the passenger side kick panel and spray all the contact connections with contact spray cleaner and then use dielectric grease on all plugs as Dino Dino suggested. Since the electrical contacts got wet and dried out, they will now start to corrode over time due to the passage of electrical current. You don’t want to put it off because the car will begin to act crazy again in the future, usually at the most inopertune time. Ask me how I know!

 

WELP! looks like I will be purchasing a new box. I think i was too late. The turning signal didn’t go off, and it has been sitting in my driveway, getting hot from the sun. I thought that would’ve helped out, but it’s still on. I haven’t been able to drive it becuase if the signal, so I will buy a used BCM and hope for the best. If my problem doesn’t resolve, I will return it and get a new car.

 

Honestly I think this is the worst issue with these cars. Ford really F-ed up the design: between the cavities under the cowl that love to collect water (and no drain properly), the apparent misalignment of the firewall "gasket" causing water to leak through the holes, and slapping one of the main power/logic distribution boxes right where that water ends up. But thanks so much for that little white foam flap over the top of the box; that's make it all okay.

Such a shame.