jmmartin

Just my two cents worth, but after spending over 3500 on tracking down this problem I found the cause of MY problem. Like so many of us I had the shaker 500 installed by the factory. Once I got the car I had it replaced by a pioneer in dash navigation unit. I had it installed by a very reputable dealer, one I knew and had used for many many years. I had ONLY replaced the head unit. When it got replaced I kept having the amp pop issue when turning the car on. Upon taking it back to the installer they proceeded to fix the pop issue. Come to find out after several attempts to fix the amp pop the installer wired the amp tun on wires, those light blue/greyish wires in the small harness to a CONSTANT hot wire. This eliminated the amp pop, but kept the factory amps hot all the time. This constant on for the amps IS NOT factory. They are meant to loose power after a few seconds of the ignition being off. This WAS the cause of my battery drain. A very simple fix, that I came across one day with a test light on my own. I hope that this may help someone else.

157dB

This guy is on to something there...

kc5mhb

He could well have a valid draw from say... a bad amp. I spent 9 years working with police cars and gear dealing with draw on batteries from bad strobe power packs, radio transmitter diodes causing the radio to partially transmit, etc. The best thing to do is get a clamp on DC amp probe and clamp it over the positive lead of the battery with the key off, doors closed and no lights, etc. on. Make note of the current draw on the battery and then start pulling the fuses that could possibly cause a draw, like: clock, radio, amps, and get it down to just the computer. Each time you remove a fuse note the different amperage. Unplug the computer last. This should leave you at 0 amps draw and with enough information to find the problem. Current draw from each component should be available from Ford in the service manual ( not sure but I would think if a mechanic were troubleshooting, he'd have to know those values for reference) or from another member that can do the same tests as you. The item that is drawing more than the specifications state it should at standby and at full power more than likely is the component failing. I've seen car PCM modules in Crown Vics pull more current than the rated value and the two way radio blamed for the battery drain. The more stuff there is connected to a battery, the more drain there is especially in today's cars with all the computer stuff. Oh don't forget that if you have RKE, you may have a malfunctioning door lock solenoid or trunk release solenoid. I'm not a certified mechanic, but these are some areas that I would investigate. Replacing the battery just bandages the problem where I believe you are looking for a solution. By the way if your battery was run completely dead at least once, the chances of it having a dead cell are likely and it won't hold a charge as well as a battery that was never run dead.

Hope this helps some.

kc5mhb

Using a test light on a vehicle with an airbag is not recommended. Invest in a $20 - $30 Digital Multimeter. That way if you are testing wires or fuses, you don't accidentally set off the airbag.

05AV6

Ok here is what I have concluded concerning the dead battery syndrome. It is true that the shaker still uses power when the car is off. It uses the power to maintain your settings and whatever else the factory decided it needed to do. So if you don't drive your car, as I don't for long periods of time (weeks) the battery will die. The slight power draw is not the main reason, but it is part of the problem. When the voltage in the battery drops below a certain value(what this voltage is I have not been able to determine) but when it drops the shaker will do the following: It will cycle through all cds in the changer, just as it does when it initializes right after you apply power to it. It will continue to do this for hours until the battery is completely dead. So the dead battery is caused by the shaker, but the problem actually is caused by not driving the car and allowing the alternator to keep the battery at full voltage.

157dB

Thats it.
Along with the shaker amps that dont turn off unless you
turn off the radio before the acc delay times out...

The standby amp draw should be low enough for a 6 month
sit but its not for some reason.

Snakebite64

Mine is out of the car for 7 months of the year so all is well