I was given this Ford F87F-18C815-BB factory tuner/cd player to see why it's draining the car battery to the point where the car won't start. It has already been removed from the car. I found the pin outs here:
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According to the owner, only the antenna and J1 were being used. By the way, since the radio has been removed from the car, the battery does not abnormally discharge.
It's been a while since I've powered up a car stereo. Do I need 12V on pin 3 (start), pin 4 (clock), pin 9 (battery), pin 10 (run:acc)? Is the "clock" the actual time of day display or is it the internal clock for the system processor(s)? Are pins 1 and 2 (illum +/-) just the 12V input that power whatever accessory lights there are? Can that be jumpered to the 12V line as well? Is it ok to common ground the illum - pin to pin 11 (radio gnd)?Basically I want to begin by putting it in standby mode and measuring the current. Also, does anyone know where to get a schematic for this unit?
This radio appears to be for a late 90s-mid 00s Ford. If the car still has the factory battery, replace it. If the battery that's in there now is more than 5 or 6 years old, replace it. You and the car owner will be happier. :)
My guess: apply power to pin 9 only to simulate the key off position.
Apply power to pins 9 and 10 both to simulate the key on position.
I don't know what pin 3 (start) does, but I suspect it might be for "load shed" when you turn the ignition key to "start", so the engine starter gets the maximum possible juice. Some cars do this by having two different "run" wires from the ignition switch - one gets dumped in "start" and the other doesn't - but I can see them just using the "start" wire as a disable as well.
"Clock" is probably either a constant +12 V to keep the clock running, or maybe it has to do with when the clock is displayed. (Like, maybe the body computer sends 12 V to it when you open the door, so the clock comes on with the dome light.) If it's constant 12 V, then I don't know why it doesn't just use pin 9, but maybe they wanted to put it on a different circuit.
Probably.
In the car, they may get fed from a rheostat or PWM box so as to have something less than 12 V on them. You might apply something like 6 to
8 V DC to pins 1 and 2, only, and see if the display or buttons start to light up. If that looks good, then ramp up to 12 V. If 12 V looks good, then yeah, you can just connect pin 2 (illum -) to pin 11 (radio ground) and pin 1 (illum +) to either pin 9 or pin 10. If 6 or 8 V DC makes the display or buttons light up insanely bright, then go down on the voltage a little.
It probably exists on two hard drives at Ford (or their supplier) and nowhere else. A few repair places, like the one you linked, may have one, but they probably want to repair your stereo for you rather than give (or sell) you a copy of the schematic. I wouldn't hold my breath waiting for one.
I powered up the unit with by putting 12V to pins 9 and 10. With the unit powered on and no load or signal, the draw was about 545ma. In standby mode, the current draw was about 4.5ma. I was checking the illum terminals and decided not to put 12V to illum + and ground because illum - terminal was not grounded. However I did put an ohmmeter across the + and - illum terminals and it was 4.2 ohms. There are 12 lamps on the display board. They are not in parallel.
I'm going to reinstall the radio tomorrow and see how these numbers compare to the current drain from the car battery.
I have no idea of possible similarity. I troubleshot a 95 olds running battery down. Auto antenna down sensor was bad, producing occasional pulses to antenna motor. I disconnected motor.
This shouldn't kill a car battery in good condition. I have heard various numbers for the acceptable "key off" draw on a car battery but
20 mA is usually somewhere in the ballpark. This is for everything in the car - the radio station memory, a clock, anything the ECU needs, security system, etc. 20 mA is 0.48 amp-hours a day, or 6.7 Ah in two weeks. A car battery is very very roughly 50 Ah plus or minus [1]; with
6.7 Ah gone it will probably still start the car. ("Airport time" is one name for this - you should be able to leave the car at the airport for X amount of time and it should still start when you get back.)
You might poke at the harness side of the connectors with a 12 V test light before you reinstall the radio. Maybe it's not getting the message that it could go into standby - short to battery power on the "hot in run" line?
If this car has any aftermarket stereo equipment wired to the factory head end, you can assume this was done incorrectly and be right about half the time. Other sources of automotive electrical fun include aftermarket trailer hookups and driving lights.
If the car has a trunk light or underhood light, look to see if it's shutting off correctly when the trunk/hood is closed. This can be a hard-to-catch source of battery drain.
Matt Roberds
[1] Yes, I know they are not rated by their manufacturer or sold this way. If you use one like a deep-cycle battery instead of a starting battery, you get roughly 50 Ah. Yes, it's not a good idea to use a starting battery like a deep-cycle. The 50 Ah number is just there as a reference for things like this.
Do you remember how often? Roughly? (Although a 2000 Toyota might be a lot different. )
Hmmm. That's a good hint for me. I started having trouble when it started getting cold. When it got really cold for a week, the antenna didn't go down all the way. I had to push it down to the bottom, so maybe when it seems to go down all the way, it really isn't.
Since it's cold and I'm in a bad mood, I only looked for the drain in changes I had recently made, and that didnt' work. I haven't felt like looking beyond them, but this sounds like a real lead. Never had a power antenna before. As my mother would say, Something else to break.
BTW, I'd be on top of this if I didnt have a Battery Buddy. It disconnects the battery when there is still enough juice to start the car. I love it. The first one lasted 25 years. But I don't think they sell them anywhere now. The Battery Brain seemed to be the successor, but it seems to be out of business and the model I wanted I can't find. Glad I bought the 2nd Buddy before the first one broke.
Some of you guys could make money reviving the Battery Brain or designing your own.
Except then, the radio would likely keep playing. Even if it had a separate amplifier, that amp is probably on when the radio is on
But even if no sound came from the radio, if the power were on, the station display would be on, and seek and scan, etc. would work.
Or glove box light.
Hard to belive, but I once installed two burglar alarms in the same car, and that ran down my battery. I thought the second was just a pager transmitter that would run only when the first alarm told it to, but it turns out it was sensing current changes all the time.
However, in this car the problem went away when the radio was out, so if the problem comes back when the radio's back in, and out when it's out again, that's a big clue it's the radio.
I disconnected battery with motor off. Monitoring current 10 amp scale. Waited till computer went into standby and watched. Motor pulses would start every 15 to 30 seconds. I went into car to listen for relays. Heard noise coming from rear trunk.
This turned out to be quite the adventure. I got a little more information from the owner. The problem started when the parking brake was pushed down. (It uses a foot pedal for the parking brake). Somehow her foot dislodged the connector going to something around the clutch pedal shaft. It has six terminals and I'm guessing it's some sort of sensor that detects the position of the clutch so you can start the car? I removed the plug and checked for damage. It looked fine. I did take a reading of the battery current before I put the radio back in with everything off before I started troubleshooting. The reading was 0. Then when I was using my meter later on I noticed that the DCV button was pressed in and not the DCAmps. At some point I measured .22A from the battery. I put the radio fuse back in (somebody had pulled it out so the radio wouldn't be draining the system) and measured the current. I jumped two about 2 amps. I wasn't writing this stuff down but I think that's what it was. Next I pulled the radio out again and left the fuse in. It was still reading too high. Then I pulled the fuse out and it was still reading too high. Huh? I proceeded to turn "off" (though I can't specifically remember that it was even lighting up) the dome light by moving the dome switch to one side. It's a three position switch so I figured one of the other choices was always off and the other position would be always on. The light didn't come on so I figured I made the right choice. Later on I found out that those other two positions of the switch were for, always on left lamp and always on right lamp. All these little details that you don't think about beforehand.
So now both doors are closed to make sure the dome lamp won't come on. The radio and Fuse 29 is removed. The current from the battery is in the 1.8 amp range. Great. I've done nothing but inspect the system and things are getting worse. Then I looked at the schematic
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There were four other lines that distributed standby power to the car. They were the cigarette lighter, flasher, instrument panel, and generic electronic module / central timer module. I pulled those fuses one at a time and went back and measured the current. After pulling the lighter fuse, the current drop to about .8A. Pulling the flasher fuse had no effect. Pulling the instrument panel fuse lowered it a bit more, and then pulling the last fuse dropped it down to near nothing. I put on my magnifying glasses and took a good look at the cigarette lighter. There was some rust or corrosion in there. By the way, the receptacle itself was not covered/protected so it made sense that it was getting to look a bit rusty. I took a sharp ended pick tool and started to scrape away at the corrosion. I put the fuse back in and the current didn't spike up. In fact with all the fuses put back in, the current leveled off at .22A. I didn't know if this was an acceptable reading or not. One of my friends was visiting with me so I asked him if I could remove the battery cable from his 2001 Honda and check how much current was flowing from his battery in standby. It was identical .22A. I'm still waiting to hear back from the owner if the battery made it through the night or it had to be jump started. That's usually good news when somebody doesn't call you back when you ask them if your repair went well, isn't it?
Yeah. There will be at least one contact that doesn't close until the clutch pedal is fairly far depressed; it is there to prevent the starter from running unless the driver has stepped on the clutch. (It also prevents a smart driver from doing something clever, like using the starter to "walk" the car out of an intersection, off the railroad tracks, etc.) If the car has cruise control, there will be another contact that changes state when the clutch pedal is barely depressed; that one is there to cut out the cruise control if the driver uses the clutch.
This is a good way to get lost in the middle of an adventure. :)
This page has been saved by Internet Exploiter... as an email... with Quoted-Printable damage. Maybe the least useful format that it was possible to use, which explains why it's IE's default.
Does the car have more than one cigarette lighter socket? An extended- cab pickup might have an extra one in the back seat. Sometimes people add one in the bed for accessories... sometimes they even get it on the same fuse as the one in the cab!
I have seen new cars that had a "no smoking" package from the dealer; the "ashtray" had a flocked lining to serve as a small storage bin, and there was a plastic plug with handle in place of the cigarette lighter element. If the lighter socket on this car is in a place where it is liable to get drinks and debris in it, finding one of those plastic plugs (dealer? junkyard?), or a rubber stopper with a bolt in it for a handle, might be a good idea.
That's kind of high. In 24 hours that is 5.28 Ah gone from the battery. That will run the average car battery down to nothing in about ten days.
Some cars have solenoids on the front seat belt reels that allow the reels to spin more freely when you are getting in and out of the car. Usually, as soon as you hit the unlock button on the remote or open the driver's door, the solenoids will turn on. They stay on until either
1) the engine starts or 2) a timeout in the range of 5 to 15 minutes expires; if you are standing there with the engine not running, you can sometimes hear a little "tick" from the seat belt reel when the solenoid turns off. This might account for some of the current draw you are seeing.
A few newer cars start getting lots of things ready for you when you open the driver's door. Toyota hybrids will turn on the electric vacuum pump (which provides brake power assist when the engine isn't running) and possibly a few other things before you have turned the key. These eventually time out as well, but the current draw from the 12 V battery might be surprising for the first minute or two.
Preliminary testing yesterday indicated that the power antenna works okay.
Although it's conceivable that when the battery was in better shape, it was the antenna that dragged it down, buit now the antenna is okay, and the battery is so bad that the factory burglar alarm (crummy as it is) is enough to run down the battery if I don't drive for 40 hours.
That's actually a better design. If your hydraulic brakes fail, hold the foot brake release handle so the brakes don't lock and then use your foot to apply the "hand brake", "emergency brake". . You can use it like the regular foot brake. I hate the hand brake between the seats.
On some cars there are 3 fuses for the radio. GM, for example. I think you talked aobut this before. One for the clock, so it doesn't stop when the car is turned off, one for the dash lights,, and one for the radio itself.
When you're miy age, you'll write it down. But I give you a lot of credit for using a meter. It's hard to get anyone to use a meter. (Anyone who doesn't read SER, at leat)
I know that feeling. When I was 19, the first week I had my '50 olds, the battery was dead every monring and I had to take my mothers car.
Short, Doconnect, Short Disconnect, Short, Disconnect, no short!!! Reconnect last disconnected wire. No short, Reconnect wire before that , No short, Reconnect wire before that. No short.
Up and down, up and down, 3 or 4 levels, 3 or 4 found tirps, and in
1950 there were no quick disconnects.
Finally found it. Glove box light. Every time I got close, I opened the glove box to get something and if it was closed well before, I closed it badly. If it was closed badly, I closed it well. That was also what drained the battery.
Snmeone may have wired something to the cig lighter circuit. I use that alot because I almost never use the lighter, so it doesn't interfere with add-ons.
If you have a decimal point, please put a zero in front of it. With my monitor, it's about the only way I can tell it's there. Right now it looks like 22 amps.
There was a caller on Cartalk where animals shorted the starter cable and the car moved "down the driveway" which was up a hill, across t he street, and almost went over a cliff.
Hey, did Indiana Jones take notes?
What the heck is .mht and how come IE reads it but maybe not Firefox?
I think I remember Pat Voss saying that if a #54 light bulb would light with the current going out of the battery, it was too much. #54 is the smallest spherical lne, back when lightbulbs were lightbulbs and didn't speak some European or Asian langueage. Someday I have to find out how many hundredsths of an amp is a $54.
Good to know. I will proably be able to use this in about 7 to 9 years.
I always have problems with left push down brake. I never had problems with right center pull handle system. One fault is left hand salt corrosion. Sometimes they not release. Sometimes you got to pull up to turn lamp off. I'm always afraid to use the push emergency brake. It's mostly a parking hold brake, if it works.
I thought dome light, was a Pittsburgh thing. It should be a hood light, Britain.
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