Battery Light.........

bushpilot

Full Access Member
Joined
Aug 2, 2005
Messages
5,815
Reaction score
4
Location
Tomball
I have an intermitant battery light coming on. The Battery "Gauge" reads normal.

This morning I put a voltmeter on it and it was reading 14.8-14.9. On the way home the meter dropped to 14.3 and the light went out.

I wonder if I have a voltage regulator sticking on me.


Tbar

well i guess im confused...you say the "gauge" reads normal (which
correct me if im wrong, infers that youre looking at the factory
DASH supplied gauge)....then you say you put a voltmeter on and
it and drove it....wheres the volt meter connected (power/cig outlet ?)

the only time ive see a "charge" light come on, on other cars/trucks,
it meant the alternator WASNT charging (ive never seen one come on
because the alternator was OVER CHARGING...but then i dont know if
our trucks have that capablity or not).

if youre measuring voltage w/ the truck turn off, then youre only
measuring the batteries...and if youre seeing more than 13.4 volts
from the batteries then perhaps you should isolate the batteries and
see what each batter measures by itself.

im not familar w/ shorting plates in a battery...so im not sure if that
could produce HIGHER readings (in a battery voltage test) or not.

load test the alternator and see if you can get that regulator to
stick is the only other thing i can suggest.

i have been told (but have trouble believing it completely) that our
alternators are computer controlled and raise and lower its output
based on threshold demand...if thats the case could you have had
a heavy drawl or short that was was making the system THINK
the alternator needed to raise its output ?
 

Tbar

SDD STAFF/Moderator
Joined
Apr 6, 2005
Messages
2,673
Reaction score
10
Location
Texas
My instrument cluster has a battery "Light" and a battery "Gauge". I was using my "Multimeter" wired through the cigerette lighter for better info.


Tbar
 

metzer.hr

METZ44
Joined
Aug 9, 2007
Messages
23
Reaction score
0
Location
Tunkhannock Pa.
I had the same issue this summer. I had my alternator checked and I had a bad diode. The FORD tech told me that is why it only came on some of the time. I recently had to replace both of my batteries this month because I drove all summer with the light coming on and off.
 

VALKYRIES

SDD Junior Member
Joined
Jan 4, 2008
Messages
24
Reaction score
0
Location
Fort St John BC Canada
Battery light.....

I checked my alternator some years ago. The diodes were within 0.048 volts of each other I have the readings somewhere here and the capacitor was 0.015 microfarads and meggered that windings at 1KV according to the comtechs at where I was working. The case that I am tring to make is that I dought if the Ford techs were able to measure what they should. SORRY TO THE REST. You should have had him write his findings down to be verified later or some time.( This just bye another part is too expensive) This is what cryslurr has had me do to fiz my do-g-. Your battery should at full charge be 2.2 volts per cell X 6 so 13.2 volts is full charge. When cumins had mine took it for a test drive and saw blue smoke coming from the alt and the diodes were VERY hot to touch with my thumb and it checked out as above. If a techy can't write down what he finds ( yes one will pay more for the info) then he is no good. Very sorry but have been burned tooooo many times to trust them!:rant
 

CHPMustang

Senior Member
Joined
Apr 6, 2005
Messages
6,352
Reaction score
2
Location
Plano,TX
14.3 has been the norm for our Excursion Tbar,that's at idle with no lights on.

Could be an overcharge possibly. Try going back to the retailer and swapping out the bad unit with a replacement,check to see if it's in stock first of course:sweet
 

roosterdiesel

Earl needs B100
Joined
Apr 6, 2005
Messages
1,763
Reaction score
0
Location
Amarillo,TX
i have been told (but have trouble believing it completely) that our
alternators are computer controlled and raise and lower its output
based on threshold demand...


When I had a fuse blown under the hood I got a Batt light on mornings below 30F last winter. It would throw a Dual Alt DTC when I scanned it. I believe the dual system is PCM controlled, not sure on singles.
 

bushpilot

Full Access Member
Joined
Aug 2, 2005
Messages
5,815
Reaction score
4
Location
Tomball
14.3 has been the norm for our Excursion Tbar,that's at idle with no lights on.

my personal experience is that the 7.3's put out higher voltage at idle (as i understand it the 7.3 has a smaller pully on the alternator).

When I had a fuse blown under the hood I got a Batt light on mornings below 30F last winter. It would throw a Dual Alt DTC when I scanned it. I believe the dual system is PCM controlled, not sure on singles.

thats what ive been told about the Dual Alt systems...the 2nd alternator
is more like a backup or stand by to the primary alternator.
 

Members online

No members online now.

Forum statistics

Threads
30,517
Messages
266,071
Members
14,629
Latest member
Colvinecoboost14
Top