We just bought a 2016 Explorer XLT and have been dealing with a parasitic battery drain. We replaced the battery right away, but the car still dies overnight. No lights, screens, or sounds are active, and the key fob is stored far away.
I tested the battery with a 20A multimeter and found it pulling around 5.5A at rest! I’ve read it should be closer to 50mA (0.050A). I pulled every fuse in the engine bay and under the dash one by one, but the drain didn’t drop. I disconnected the small cable off the main positive battery cable, and it turns out the small cable is carrying all the current. The big cable had none. Then I traced the issue to the cable shown in the picture (red arrow). Does anyone know where this cable leads or what I should check next?
First, make sure to let the car sit for 10-20 minutes after shutting it off. This gives all the modules time to go to sleep. If you test too soon or with a door open, the modules could still be active. My guess is one of your modules isn’t going to sleep.
@Peyton
I’ve tried waiting and also pressed the hood switch so the car thinks the hood is closed. All doors and the hood are shut, the car is locked, and the key is far away. I also think it’s a module issue but don’t know which one to check next.
@Kingsley
It’s hard to pinpoint without being hands-on, but since you’ve found the general area, you’ll need to follow the chain and test everything connected to that cable one by one.
Peyton said: @Kingsley
It’s hard to pinpoint without being hands-on, but since you’ve found the general area, you’ll need to follow the chain and test everything connected to that cable one by one.
Do you know where this specific cable goes or where I could find a wiring diagram?
Have you checked the relays? The Ford website has user manuals with a section on fuses and relays. You can also find videos on YouTube about parasitic drain testing and how to test relays. A good mechanic should be able to help, too.
That cable in your picture is pretty hefty and looks like it’s designed to handle a lot of current.
Did you mess with the Sync system? When I upgraded mine, bad programming caused the screen to stay on, leading to a battery drain. At night, you can see if it’s staying lit.
Finnley said:
Did you mess with the Sync system? When I upgraded mine, bad programming caused the screen to stay on, leading to a battery drain. At night, you can see if it’s staying lit.
