Help - I have a 2015 Super Crew that I bought for my son who just completed his Eagle Rank. We are having issues with the hazard lights randomly turning on while driving or while truck is off and parked. If it helps with diagnosis our horn wasn't working prior to this even with a replaced fuse. We weren't super concerned (what 16 yo needs a horn), but now horn is working (although also gets stuck on).

Was thinking of learning to replace the flasher relay just in case. Would love any other thoughts. We've ruled out the battery and user error at this point since it activates itself while otherwise being driven/operating normally.

Please help a single Momma out with suggestions here!

 

The hazards are driven by the Body Control Module(BCM) on your truck. The horn is also driven by the BCM. I have seen many weird electrical issues due to low voltage, especially the systems that deal with security of the truck. Both the horn and Flashers are part of a security feature that can be activated when the battery is weak or disconnected from the vehicle. I would check the current state that battery is in (AutoZone, Oreilly, Interstate, can all do this). if it is in anyway weak, replace it. If it test good then it may be time to bring it to a repair facility and have them check for any signs of trouble within the BCM.

 

gorachie
When you get this issue resolved please post solution so that others can gain insight.
Jimboy

 

I have also had issues with my EMG Flashers turning on. Both times found a device that was plugged into the 12V outlet was on and ran the battery down over several days. I 12V outlet I use for the device seems to be switch off and on when the key is turned off and the door is opened much like the radio does. It continues to play until it times out or you open the door. The radio always turns off when the door is opened but the 12V outlet does not turn off every time. In my case I was out of town both time for 3 + days and my flashers started flashing after the 36 hours as per my neighbor. The battery was so low, the remote nor the keypad would unlock the door. I had to use my key and the truck would not start. I pressed the EMG BUTTON on dash and the lights turned off for about 2 minuted but came back on. I jump started my truck with a 12V BOOSTER BOX and truck cranked up but things were still not right. I let it run for 30 minutes and it restarted. Lights started flashing after 30 minutes, so I checked the battery voltage with digital meter. ONLY 11.52 volts. I started truck and voltage went to 13.7 volts. Drove for a while and had the battery and alternator checks and they were fine. No more issues. I WOULD SUGGEST THAT IF THIS HAPPENS TO YOU CHECK THE VOLTAGE AT THE BATTERY WITHOUT STARTING THE TRUCK. ALSO CONFIRM THAT YOU HAVE NO DEVICES PLUGGED IN THE 12V OUTLETS. ALSO CHECK TO CONFIRM THAT YOU 12V OUTLETS TURN OFF AFTER A TIME. NOT SURE HOW THIS IS SUPPOSED TO WORK, BUT MINE STAYS ON HALF THE TIME WHEN YOU OPEN THE DOOR WITH THE ENGINE SWITCH TURNED OFF. HOW THIS HELPS. ps: This happened to me twice about 3 months apart, but just found the issue with the 12V outlet staying on and running my battery down.

 

As the issues continued to get worse, I was able to get a service appointment at my local Ford Dealer, Akins Ford in Winder, GA. As we suspected the BCM was bad. A windsheild leak on the passenger side where the BCM is located had damaged the BCM and 3 of the connectors. The first issue was to stop the leak by resealing the windsheild by removing it and resealing it, but this is not an easy job and the windsheild cracks about 90+ percent of the time. So after the NEW windsheild was installed, the BCM and the damaged connectors were replaced. All seems fine and no apparent leaks so far. Lots of rain and 4.5 inches thanks to the storm Henri. The truck had a leak from the factory on the drivers side and they stopped that but I guess it was leaking on the passengers side. This is a 2015 so not much chance for free repair. I'm just happy that I was able to get it in the shop and they were able to fix it. It took 14 days total at the shop. Parts were the main issue.

 

Mine started doing this the other night. My neighbor calls me and tells me hazards are flashing. Unlock it, still flashing. Press the hazard button, still flashing. Only way they turn off is to start the truck, then press the hazard button. Then today I was in the garage working and I’ve had to do this about 4 times in the last hour and half. 🤬🤬🤬

 

Well mine did different things on different day and alway after a heavy rain. The first issue was the alarm activated and the horn blew continuesly. My neighbor woke me up. Had to pull the horn fuse to stop horn. It stop after that until the next rain and the flasher started. I was out of town, so they flashed until the battery when down and the truck would not start. Jumped off and drove about 30 minutes all seem ok. But each time it rained something else would happen. I disconnected the battery several times and when I went out of town. The dealer checked the battery and load tested it and it tested good. The battery was about 2 1/2 years old but still in warranty so they replaced it free. Did not really help. I had to disconnect the battery everytime I drove it, even down to Walmart. It also effected the door lock and would unlock the truck on its own. I kept a pretty good record of issues and date, but I did not make the rain connection until towards the end. Luckly the local Ford dealer was able to work me in and completed the work within 14 days.

 

Wow! I’m not experiencing anything with rain. It’s been dry when it’s been going bonkers. Only things i added were *** eliminator (which doesn’t even work) and XB hybrid headlights. I’m going to disconnect the *** eliminator tonight and see if that makes a difference. Then I’ll move on to the headlights if it still does it. I have time until the dealer can get it in.

 

Good luck in your search for a easy fix. I only started having issue this year and did not have water inside the cab. The water leaked behind the passenger side kick panel behind the fuse box. The technician said that the damage to connectors is what caused the BCM to fail. Really hard to check without removing your glove box and the kick panel. Hopefully, you can get it into the shop before it gets worse. GOOD LUCK.

 

I got DTC codes for head lights(grounded?) and horn(grounded). Lights seem to work fine but horn does not work. I suspect the BCM. Recently had water enter the cab(bad windshield install). Passenger floor was soaked. Does anyone know where the BCM is located on a 2019(limited)?

Thanks.