Friend of mine has been dealing with an intermittent draw. He's had this car (2009 Crown Victoria, ex-police) to several of the best automotive electrical shops in the area, to no avail. The problem he has is that every week or so, the car will kill its battery overnight. What's made this problem especially difficult to trace is that it only exists on those nights. If you don't know which night it's going to do it, there's no way to trace it.
I gave it a go on a few different nights, but never caught it in the act. The primary suspect is the "Lighting Control Module", but that has never been verified.
The best recommendation he was given was to attempt replacing the LCM and then basically just see what happened. He's already purchased a new battery for absolutely no good reason and was not ready to try shotgunning any more parts out of little but hope.
He again visited some more shops experienced in electrical, and even a shop that only fixes Crown Victorias, and no resolution. At this point, he was desperate. He was ready to get rid of the car, rather than continue to deal with these issues. He needed a permanent solution, fast. I had only one idea:
What I did here was to route all of the battery grounds through an 80 amp continuous duty solenoid. The solenoid is fed power by a small rocker switch under his dashboard. By controlling the ground of the battery, rather than the positive circuit, I only needed to run one wire from the dash to the solenoid. The switch is still able to access power from the car's power circuit. But since the ground is cut off to everything else, only the grounded solenoid can make use of the vehicle's power system.
When he parks for long period of time, he turns off the rocker switch, and power is cut off to the whole car. When he goes to drive, he turns the switch on, engaging ground for the entire vehicle and allowing him to drive it.
This is obviously not even remotely as good as finding the true problem and correcting it, but he has 3 children he needs to move around during the day and was out of time, money, and patience. Not a perfect solution, but a solution none the less.
He made sure to toss a 1/2" wrench in the glove compartment so he can join all the grounds on the same post, should there be a failure of the solenoid, switch, or wiring. He can continue to start and drive until a repair of this new system can be performed.
I gave it a go on a few different nights, but never caught it in the act. The primary suspect is the "Lighting Control Module", but that has never been verified.
The best recommendation he was given was to attempt replacing the LCM and then basically just see what happened. He's already purchased a new battery for absolutely no good reason and was not ready to try shotgunning any more parts out of little but hope.
He again visited some more shops experienced in electrical, and even a shop that only fixes Crown Victorias, and no resolution. At this point, he was desperate. He was ready to get rid of the car, rather than continue to deal with these issues. He needed a permanent solution, fast. I had only one idea:
What I did here was to route all of the battery grounds through an 80 amp continuous duty solenoid. The solenoid is fed power by a small rocker switch under his dashboard. By controlling the ground of the battery, rather than the positive circuit, I only needed to run one wire from the dash to the solenoid. The switch is still able to access power from the car's power circuit. But since the ground is cut off to everything else, only the grounded solenoid can make use of the vehicle's power system.
When he parks for long period of time, he turns off the rocker switch, and power is cut off to the whole car. When he goes to drive, he turns the switch on, engaging ground for the entire vehicle and allowing him to drive it.
This is obviously not even remotely as good as finding the true problem and correcting it, but he has 3 children he needs to move around during the day and was out of time, money, and patience. Not a perfect solution, but a solution none the less.
He made sure to toss a 1/2" wrench in the glove compartment so he can join all the grounds on the same post, should there be a failure of the solenoid, switch, or wiring. He can continue to start and drive until a repair of this new system can be performed.