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As the car has been doing this for a period of time but starts OK which suggests the battery has been getting charged sufficiently, so I doubt that it's the alternator. In the main fuse/relay junction box there is a relay called the power hold relay that puts battery power through a hot at all times 20 amp. fuse to the PCM when the Ign. switch is at On or Start. After checking the battery connections as suggested, I'd swap out this relay. It should be common knowledge by now, but I"ll repeat it.......NEVER, EVER disconnect the battery when the Ign. switch is selected ON, including any attempt to see if the alternator is producing current. It's a good way to zap the PCM and/or the alternator. The FSM for any modern car will have this warning.
 

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As the car has been doing this for a period of time but starts OK which suggests the battery has been getting charged sufficiently, so I doubt that it's the alternator. In the main fuse/relay junction box there is a relay called the power hold relay that puts battery power through a hot at all times 20 amp. fuse to the PCM when the Ign. switch is at On or Start. After checking the battery connections as suggested, I'd swap out this relay. It should be common knowledge by now, but I"ll repeat it.......NEVER, EVER disconnect the battery when the Ign. switch is selected ON, including any attempt to see if the alternator is producing current. It's a good way to zap the PCM and/or the alternator. The FSM for any modern car will have this warning.
Thanks for the info, now I know. I don't see why it would affect anything since it is electrically the same with or without the battery, but if the factory service manual warns against it I won't suggest it to anyone again.
 

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Old Phart
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Batteries & alternators

Sailor, no disrespect but you are wrong on this one. The alternator can charge a normal battery, but they are not made to charge a discharged battery. A car should, and will run off just the alternator, that is how cars are designed. The batteries sole purpose is to turn the starter on start up, after that the car runs off the alternator, with some draw going to bring the battery up to full charge. A car will draw from the battery sometimes when sitting in traffic or idle with the ac running. I could be wrong, if you can name an instance when it has killed a good alternator, I'd like to know. All I know is it is a simple and reliable way to see if the alternator is working.
Sparks, no "dissin' " here either, just some extra info..

Your description of where power comes from and when is perfect, but there are some special case reasons why "logical" test corollaries aren't a good idea, and the "dead" battery instance also depends on the details...

As to "dead" batteries, correct as to charging a totally "dead" battery - when there's no power at all from the battery the alternator won't produce any output so no charging. Engine prob. won't run either for lack of electricity, but in a few cases it may run, using all the power avail. so there's still no charging output - bunch of odd special case possibilities here, general rule to make testing valid is to use a known good battery when checking the charging system on any vehicle to get valid results & avoid the odd cases that may give confusing results. So, severely discharged batt. needs some outside source charging before the car's system can do the rest of the job. Low batteries (often called "dead") that need a jump to start the car will recover from normal alternator charging, but a short drive isn't adequate...

Pulling the batt. terminal to check for adequate charging dates back to the days of generators & cars with no electronics - a more "robust" system with regard to voltage spikes...

While doing this doesn't always cause damage, the potential is there & risking severe damage to alternators & electrical components from voltage spike when disconnecting the battery just isn't worth it.

My best "proof" can be found if you look up battery switches, either racing safety disconnects, or marine versions for multiple batteries. Cheaper versions have no alternator protection circuit, and carry warnings about possible damage if battery is disconnected while engine is running.

[cheers]
 

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Wow they would not have gotten one dime if I left with same issues unsolved.They would have removed what they installed , that just sounds more like part swapping then diagnosing.Hear a lot of this now days.Sorry but part swapping gets very costly, just sounded like you are paying to train mechanics.I just would not have paid nothing for parts unless vehicle was repaired.Now I would not pay the bill either if a shop that replaced my ignition module ,plugs , wires, cap, rotor and coil to solve a misfire.This just tells me they just part swapped until they found the problem.Problem is, more and more shops do this instead of finding the problems through proper diagnosing.Demand either they find/fix the problem or remove and refund for all the non corrective parts they installed along with the part swapping training you provided to their mechanics at your labor rate.

I would be looking at Voltage Supply/Defective cable/wire or poor cable/wire connections.Mainly the ones supplying the fuse panels.Would also be looking at grounds and their connections.Would include ECU along with wiring and connection connectors.Best to stay with one place that is trustworthy for repairs and not just replacing parts and charging without resolving the problem , as taking your vehicle to multi shops/people you keep repaying to have the same things checked/retested.Don't pay for parts if you leave with original problem.Ask questions why and what each part your charged for is and why it was replaced.Usually electrical switches and sensors don't all go bad at once or very very rare.If they tell you they are stumped but here is a bill for 5 parts plus install and Diagnosing labor charges, only pay for diagnosing labor time, remember your car hasn't been fixed so why did they put new parts on it but its still broke and doing same thing, They can swap the parts back out or eat the part costs!
 

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Speedometer and mileage not working - check engine light battery light seatbelt light oil light and coolant light stay on on my dashboard. I recently got my fuel injection switch replaced in my 2005 ford focus zx4. The next day when I turned my car on my speedometer and mileage was not working and all lights on the dashboard stay lit. What can be the problem?
 

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If one of the diodes went out in the alternator, then very possibly AC is being applied to the battery and alot of strange symptoms would appear

Get a multimeter, set to AC Volts, see any? then you have a problem
 

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Captain TMI
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Speedometer and mileage not working - check engine light battery light seatbelt light oil light and coolant light stay on on my dashboard. I recently got my fuel injection switch replaced in my 2005 ford focus zx4. The next day when I turned my car on my speedometer and mileage was not working and all lights on the dashboard stay lit. What can be the problem?
Well, the first problem is that you've posted in a thread that was started 4 years ago. Give us a good description of what your problem is in a new thread using the yellow "New Thread" button on the previous page where the threads are listed. This will give you a wide variety of responses from our regular members, and hopefully we can solve your problem.

I'm personally interested in what you mean by "fuel injection switch"- is that a relay? There are no switches in the EFI circuit. I'd be taking it back to that mechanic and asking him why this problem wasn't there before he worked on the car.

Here is a link to the main page of General Technical Chat so you can start your own thread.
 

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Same exact thing has been happening to my 2005 ford focus zx4. Wasn't the battery, nothing in the fuse box, so now I'm replacing the alternator. By the way who else agrees that the location of the alternator is a pain in the butt?!
 

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Grounding Issue

My son came home describing a clicking noise under the dash and the headlights going dim. I removed the ground wire coming off the negative connection to the battery, sanded the paint off to bare metal, cleaned connector, used dielectric grease, tightened down the connection, and no more problems.
 

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Old Phart
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Good move & a nice first post!

Welcome to FF

When that is recommended, it's seldom believed. Tx for posting your experience with it.
 

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I had the same problem and then I found this site and a gentleman said to clean up the grounding wires on the negative side of the battery. I did and the clicking, flashing, and stalling stopped. We then added another ground off of the battery to the engine. Now it starts a lot faster. I am glad I found similar problems here because I am only out a battery saver relay I changed thinking it was the problem.
 
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