Well, I was driving my expy home from dropping off my daughter, and the radio and windows died. I tried to get it home, but before i got it home everything powered shut off; leaving me stranded.
The check engine light was on about two days before this happened.I bought an ebay alternator and I put it in.The trunk started with a jump, the check engine light was off and i was happy.
The next day while driving, i notice the voltage or battery meter had drop down to (8)eight, and then botomed out as i got home.I then went to Sears and got a Die hard battery, after they told me my battery was bad.I thought that was it. Murray's said that my old alternator was bad and the newer one was good.Well,The truck is doing it again.This sounds expensive.
Here are some clues maybe someone knows where to direct me to find this infiltrader. First pressing the brake drains the meter fast and hard.Second i found that my roadside emergency fuse for the radio,premium sound was draining the battery after the truck was off.I had aftermarket fog lights and a sound system that I got rid of after this started. I hear Ford charges 80+/hr For electrical work, oh boy! Thank you.

 

I had a simliar problem recently with my '99, except no check engine light, just the battery light came on, lights dimmed, wipers were moving at a snails pace. Started again with a jump and was able to get it home. A few days later had it checked at the dealer and they ran a diagnostic check for $80 and they ended up replacing the alternator and battery under warranty and waiving the diagnostic fee leaving me to pay only for my deductible on the warranty. No problems since they were both replaced.

Smitty

 

You are very lucky!
jason

 

Sounds like you may have a short somewhere. The alternator is not made to charge a dead battery. If you have a short that is draining the battery, they may both be bad again as the battery and alternator may be getting stressed more than they can handle.

I would start by looking for shorts. Remove the pos battery cable and put ammeter in series with it. If there is alot of current being drained, then start pulling fuses until it drops. This will be the circuit that you will have to check out.

When you removed your aftermarket stuff, did you remove all the wiring or just the components on the ends. You should probably start there if there is any wiring left as you are pulling alot of current if you can see the alternator voltage drop. One of the wires may have chaffed and could be touching the chassis.

Hope this helps.

Glock

 

thank you glock, but what exactly is a short, is that if a positive or negative wire is touching metal or is that a fried piece of wire, and how much is a ammeter? Thank you.

 

In a modern car/truck, a short is when a wire connected to the + battery terminal (fused or not) touches the chassis (or - batt term) without going thru an electrical device first (light bulb, radio, fan, motor etc). There is no resistance to limit the flow of current so it attempts to draw infinite current. When the battery cannot supply any more current the voltage drops.

Technical stuff below if you are interested.

When you have a radio connected to the battery it draws a certain amount of current. This is because the power supply of the radio has a certain amount of resistance to it and will only draw a certain amount of current for a given voltage The formula is V/R=A where V=voltage R=Resistance and A=Amps (current). Same is true for the headlights. There is resistance in the filaments. The formula is a little different where P=A*V P=power, A=amps and V=volts. So a 55W headlight draws 3.9A at 14V.

You can get an ammeter from Radio shack for $29.99 (Catalog #: 22-813). If the truck is drivable you could also go to AutoZone and they will put it on the tester for free and (I think) should be able to detect if you have a short.

Glock

 

Did they bench test your new alternator or did they test it in the truck? If they bench tested it and it was fine then the first thing I would do is to check your electrical connentions going to the alternator. I had a similar thing like this happen to me. It turned out to be too much dielectric grease in the socet of the alternator. If you unplug the alternator and look at the plug and see a bunch of clear grease in it then it could be your problem. Just clean out the excess with a Q tip and all should be well. You voltage should drop with the brake lights on. You are running 5 bulbs..... 2 for tail lights and three for your third brake light. If your battery is already taxed from the alternator not charging properly this is what it will do. When mine did this it made all kinds of interesting noises..... the door ajar light came on, there were buzzers going off the throttle wouldn't respond then it just died! It jumped right back off and drove another 4 miles then started all over again. The electrical systems on these rigs are very elaborate. They control everything from fuel to lighting. If your alternator is not charging all hell will break loose! Easiest way to check with alternator in truck is to start vehicle and check voltage readings at the battery. It should be between 14-18 volts. Or you could just simply disconnect the battery and see if it still runs. If it does stay running then the alternator is putting out enough power to run the truck. Then start turning things on one at a time. If you can't run everything with the battery disconnected then the alternator is toasted.

 

Everything you said happened to your truck happened to mine, the buzzer sounds the throttle going up and down, the whole instrument cluster lit up and without power there is no "comfortable" air ride, expy starts to ride like a ghetto UHAUL hitting switches. Yes, yes, thank you for feeling my pain. I just put a ebay alt in there and I used no dielectric grease, so that's not it. I took the alternator out after Sears said something was producting 12.2 or 12.4 while in the truck, then took it up to Murrays auto, where they put the alt in a machine simulating my belt and connectors. The screen on that test flash green and said GOOD. I am going to try the disconnected battery thing and I will post you trucking people.

 

hey, I started up the truck and disconnected the battery, positive first and the truck stopped right when I pulled the +pos off its post. Brand new alternator or wire from/to alternator? Thank you.

 

My girlfriends father told me that the problems "not" the alternator, because the radio would "not" have been the first thing to die, it wound have been one of the "last", it uses very little power. So, i think it's the radios' wiring somehow, i'll see tomorrow when a ford dealership checks it out.

 

depends on how smart the car is...they are starting to use sacraficial systems, being that the car will begin to shut down non nessecary items to keep the motor going....my friends Diamante went through this....It lost electrical devices in order, radio, windows, a/c.....anything it could sacrifice to keep the motor running...

 

Your radio doesn't use the least ammount of power. If it is an Eddie Bauer it has the MACH sound system. You are pushing three amps and 7 speakers along with a cd changer. If your truck died immediately when pulling off the + terminal I will put my $$$ on the alternator. If it only tested at 12.2 or 12.4 volts it is junk! These vehicles need 15-16 volts constant to run! It will only charge back 12-14 volts to your battery. It should also read 185 AMPS output. I don't trust Ebay at all. They probably sold you a bad alternator. Autozone will run a load test on your truck for free. They will hook up your truck to thier computer and run it through thier test. The voltage you stated is way low and if the alternator was good your truck would have stayed running with the positive terminal off the battery. Save your self a bunch of wasted time and wasted $$$ at the dealer and replace your alternator with one from a reputable parts store. Then call the seller from E-Bay and tell him you want a full refund and he needs to reimburse you for a tow charge that you incurred due to a faulty alternator.

 

A brand new one from Discount Auto parts is $229. Reman in $129. Both have lifetime warranty, so when it dies again it is free. I recommend the new one as I have not had good experiences with remans. (Florida summers are killer on electrical systems)

Not to bash, but I think the numbers in the above post are a little high. The stock alternator for a 2000 Expy 5.4L is 130A. A fully charged battery is actually around 12.8V, so you need the alternator to put out at least that much just to charge the battery. Most alternators put out 13V-14.5V (after being rectified). The regulator will decrease the voltage depending on battery charge state and electrical current demand.

Glock

 

Is your Ex an Eddie Bauer? If not then thats where the voltage difference is.

 

No it is a XLT.

That is interesting. When I looked replacement parts there is no reference to model only engine sizes, even on an OEM site. Seems they use the same alternator. Odd that they would have a different alternator for an EB that puts out a higher voltage

I'll have to check into it more. Being a bit of a shade-tree I am intrigued. Goes against what I have seen while working on cars.

Anyways Later

Glock