chargin systems troubles are back... need some ideas

[lovebite]

A couple of months ago my explroer stanrded acting strange, it was dead one morning when i was going to go to class. I got a jump from my brother and drove it around for a while which helped. I drove it around to places and didn't have any truoble starting it. then the next day same problem... dead battery, I got another jump but this time it took a good 20 minutes before it would start. I got a new optima red top battery because I have 4 100w offroad lights. Stupid me let my little brother hook up the battery and he for a second hooked the battery up backwards. After this I had to replace the alternator that died. I got the battery checked by Advance auto, they said it was good and got my new alternator (refurb) from them. Still had charging system problems. I took the alternator back and it failed the output test so I bought a brand spankin new one not a rebuilt one. this fixed most of the problem. Then the problems that were left were fixed by replcing the 175amp fuse that was bad. At this point everything was good other than the voltage gauge was always a little lower than normal all the time (voltages at the battery with it off and running were within acceptable ranges). Now I am having problems withthe charging system again. Today after failing my chemistry test I was looking at my notes in my car with it running at idle in the parking lot and this was with the radio on but not turned up, and the headlights on the battery was reading very low on the guage(just around a 1/4 a lot lower than normal). This should not be happening with a less than 5 month old optima red top and less than 5 month old brand new alternator. the battery guage goes low just when switching something like my normal driving lights on and the alternator kicks in I guess and it goes up a bit more but not verymuch at all. with this situation with my blower on and the raido I looks like it would make it so i would having the lowest reading the guage could registar. Any ideas on what in the world could be my problem?

 

[lovebite]

Just chekced the voltage of with my multi meter and with the key on and the lights and the radio the voltage is around 11.6 I think, and then with the car running with the lights on and the stock raido on the voltage is at 14. When I turn the blower on to speed 2, with the radio on, the headlights on, and the car at idle it reads 13.98

 

[robertoa1a]

Well? Maybe it runs on batteies! JUST KIDDING!

It sounds like something is still draining your battery when it isn't suppose to. Perhaps a stereo someone installed and un-installed could be the culpret.
Bad wiring by a previous owner can speek volumes. If you can look underneath the dash and seats, what will tip you off is wires taped together(bad wiring ediquete) n" stuff. Yellow, red and blue crimp on butt connectors. Take a look see.

 

[Tbars4]

...Advance may have a problem with their alternators..
http://www.explorerforum.com/forums/showthread.php?t=237162

 

[tripplec]

Does not matter what the vehical is.

Put a multimeter across the battery. Make sure the probes have a could connection.

Make a note of the battery voltage. It should be around 13V DC or just under. Otherwise the battery is low and need of charging and subsequent test will not show a higher voltage.

Start the vehical, note the voltage should be approx .5VDC higher and ideally around 14.5VDC once fully charged or approaching it. But the point to note the meter should be higher than before you started it!!!!

After a minute or two do the following. Watching the volt meter!!!
- turn on headlights (see if voltage remains higher around 14VDC but not 13 or lower)
- turn fan blower on HIGH
- turn on highbeams
- turn on rear window defogger

This represents a fairly high load in incrementing steps. If you rev the enging to 1200-2000RPM the alternator is at its maximum output and may come up higher as it should.

I suspect the reverse voltage from the battery has blown several diodes in the alternator. Replace the alternator if you had it tested. It should be a loaded output test in that these alternator should be 100Amps or higher otherwise the test incorrect.

Good luck.

PS: You could have your brothe do the appliance turning on as outlined while you observe the meter. Oh make sure he does not plant the pedal to the floor to rev the engine!!

 

[lovebite]

The alt. might be the problem from that ordeal, but after that battery incident I had the reman alt. that I had previously bought and it had failed... I think because of the battery situation. Advanced auto then replaced the alt. and I chose to upgrade tothe brand new one because of the problems I had read about on this site with the remaned ones. I could have gotten a new bad alt., the regulator could be bad, or the battery is not charged enough from my drives to class. Tripplec, When you said to turn everything on... and on high I do not think I could do this without consuming anypower that might beavailable for the car to run on. I will try doing this test with everything on and see where the voltage is and if this does not prove sucessful then I will take the alt. off and take it to napa and then Advance to have two tests done on the alt. Thanks guys I will let you know how this works out

 

[tripplec]

Take voltage readings first before starting, after with no load and with load on the system. This will be a good point of reference and clearly show whether the alt. is good and if you replace it then the reading should be higher when running and under the fully loaded electrical systems as I mention. You can do the same on a vehical without a problem to see as well.

Good luck.

 

[Tbars4]

..But as mentioned, reversing your jumper cables may have fried your alt and you may need a new alt and then, you still may need to do some trouble shooting...

 

[lovebite]

tbars, the alternator got replaced after my brother hooked up the new battery wrong with a brand new one. I had the battery tested after that incident also and it is good. I just took some more readings before taking the alt. off because its cold and there is a snow storm outside so I might wait until tomorrow to take it off and get it tested again. here are the numbers i got from the tests:
1. engine off and nothing on = 12.50 volts
2. engine off with head lights, radio and blower on half way = 11.64 volts
3. engine running(idle) with nothing on = 14.0 volts
4. engine running(idle) with radio(stock radio), headlights, and blower on halfway = 13.90 volts
this is looking like it might be the alt. or the regulator on the back
5. engine running(2k RMPS) with raido, headlights and blower on halfway = 14.24 volts

 

[team]

Your alternator seems to be doing fine with the above mentioned numbers. Your batt. with everything off is just a tad low (fully charged batt. is 12.6 volts). I would do a parasitic draw test just to make sure you don't have excessive drain with the car off. Unhook the positive, put the multimeter in series with it, turn it on amps, and make sure nothing is on on the vehicle (no interior lights, or underhood light etc.) and read how much current draw there is. It shouldn't be over .5 amp max. but perferably much less. Let us know what you got.

 

[tripplec]

tbars, the alternator got replaced after my brother hooked up the new battery wrong with a brand new one. I had the battery tested after that incident also and it is good. I just took some more readings before taking the alt. off because its cold and there is a snow storm outside so I might wait until tomorrow to take it off and get it tested again. here are the numbers i got from the tests:
1. engine off and nothing on = 12.50 volts
2. engine off with head lights, radio and blower on half way = 11.64 volts
3. engine running(idle) with nothing on = 14.0 volts
4. engine running(idle) with radio(stock radio), headlights, and blower on halfway = 13.90 volts
this is looking like it might be the alt. or the regulator on the back
5. engine running(2k RMPS) with raido, headlights and blower on halfway = 14.24 volts

I replied to the notification email but though I should post it in the thread as well.

Ok, load test with engine OFF are not necessary for this. Only the voltage before starting which is to give you a point of reference. That is it has to be higher when running!! And it is, 14v from what I see which is good and normal. Under load as slight drop of 0.1v is also normal. If you raised the RPM's to 1200-2000PRM which is about where then engine will be when driving it will likely come up even more especially if the battery is low. It's likely you are have problem with the gauge only. If the Radio, lights are normal brightness and other accessories are fine then no worries.

Good luck, I don't see a problem with the charging circuit. You must have had the radio turned off when the battery was connected. The power transistor for the Amp usually blow when that happens. Horseshoes man.... Ha ha

A lead acid battery is 13.2VDC fully charage. Thats 2.2 VDC per cell which is 6 for a 12v battery. Cheers

 

[team]

I replied to the notification email but though I should post it in the thread as well.

Ok, load test with engine OFF are not necessary for this. Only the voltage before starting which is to give you a point of reference. That is it has to be higher when running!! And it is, 14v from what I see which is good and normal. Under load as slight drop of 0.1v is also normal. If you raised the RPM's to 1200-2000PRM which is about where then engine will be when driving it will likely come up even more especially if the battery is low. It's likely you are have problem with the gauge only. If the Radio, lights are normal brightness and other accessories are fine then no worries.

Good luck, I don't see a problem with the charging circuit. You must have had the radio turned off when the battery was connected. The power transistor for the Amp usually blow when that happens. Horseshoes man.... Ha ha

A lead acid battery is 13.2VDC fully charage. Thats 2.2 VDC per cell which is 6 for a 12v battery. Cheers

Not trying to start a pissing match, but I have never heard of a fully charged battery being 13.2 volts. 2.1volts times 6 has always been what I have read.

Look at this
http://www.progressivedyn.com/battery_basics.html

http://www.yuasabatteries.com/motor_battery.asp

 

[tripplec]

Not trying to start a pissing match, but I have never heard of a fully charged battery being 13.2 volts. 2.1volts times 6 has always been what I have read.

Look at this
http://www.progressivedyn.com/battery_basics.html

http://www.yuasabatteries.com/motor_battery.asp

Sorry, I stepped aside, so it missed.....
Anyway, point was to educate and I am not going to quibble for .1 volts as its all relative. After a battery had be charged and/or the vehical is turned off. Meter the battery and is should be at 13V approx if it drops down to the lower 12v area it is likely, I say likely a sign of a weak or dead cell. Back when we could test the electrolite in each cell we could be 100% sure of the state and capacity of the battery but with most maintenance free batteries the tops are sealed with cover that don't come off without damaging them at best. If you have a battery which you can check the fluid. A fully charge cell is 1275-1280 specific gravity with a cheap hydrometer. Testing each cell in a battery will quickly identify a failed, dead or weak cell. The specific gravity will be at least 30 or more lower than the rest of the cells, ideally the should be the same or less than 10 difference. When you measure the end to end voltage the true condition of the cells are unknown and a load test is the only way to get an idea if it still has balls but not full proof since the condition of a bad/weak cell is problimatic and will catch you one day soon even in a hot day.

PS: Beer match better than P....ing cheers

 

[lovebite]

okay, finally got around to measuring the current draw. I think I did this correctly. I put the red test lead on the 10Amax unfused setting and then turned the dial to the A 10A setting that lines up with the where I placed the red test lead. I unhooked the positive terminal on the battery and put the meter between the positive terminal and the positive lead from the battery. this gave me a reading of 0.22 for what I believe is my amps being draw with the car and everything off. Is this to high meaning I have something drawing to much power? or is it good. If this is good then the selection has been narrowed down to the alt. is not putting out as much power as it should be.

 

[tripplec]

okay, finally got around to measuring the current draw. I think I did this correctly. I put the red test lead on the 10Amax unfused setting and then turned the dial to the A 10A setting that lines up with the where I placed the red test lead. I unhooked the positive terminal on the battery and put the meter between the positive terminal and the positive lead from the battery. this gave me a reading of 0.22 for what I believe is my amps being draw with the car and everything off. Is this to high meaning I have something drawing to much power? or is it good. If this is good then the selection has been narrowed down to the alt. is not putting out as much power as it should be.

You're on the 10amp range of your meter. I gather its a digital meter if it showing the . point. .22A is 220mA which is nothing at all. I have not check mine but with the computer and all sorts of electronics builtin such as door lock there is some draw. If you have over 1A then I would be suspecious.

 

[team]

your parastic draw test results are fine. And from what I am reading your only concern is your stock voltage gauge? Mine dips down at idle also with a decent load on. It is going to do this some because the alternator is not spinning very fast and can't put out as much current. Are you still having any starting issues?

 

[my98nnj]

the selection has been narrowed down to the alt. is not putting out as much power as it should be.

There is nothing wrong with your charging system. The numbers you have posted are all well within spec. As mentioned in another post, it's probably the guage in the truck thats screwed up. Again, as per the numbers you have posted, there is nothing wrong with the charging system or the battery.

 

[lovebite]

okay good. Thanks guys for all the help.