Ford F-150 battery light

10

Asked by Jul 19, 2013 at 07:21 PM about the 2000 Ford F-150 XL 4WD Extended Cab SB

Question type: Maintenance & Repair

Hi:  When I accelerate medium to hard in my 2000 Ford F-150, the battery light comes on.  When I take my foot off gas or lighten up on gas, the battery light goes off.  Any ideas what this might be?
Thanks.

7 Answers

Going to call this one as a bad ground...corroded 1/0 battery cable as it leads to ground....Battery is older than five causing the alternator to work overtime to supply a battery that is reluctant to take a charge...yes, get a New battery, wirebrush the main Ground connection...fuel, ignition and the ECU all use this ground connection...kinda messes it up because the starter motor is always asking for 300 amps through this connection, yet the ECU perhaps uses 1.5 mA~ if your battery is NEW and Fresh would say tighten the belt or replace the tensioner and arm and idler bearing (in a kit)~

3 of 3 people found this helpful.
10

Thanks for your answer Judge_Roy. What are the chances that it is the alternator itself? The battery is about six years old, but it is one of those Optimax batteries (AGM) and I think its life expectancy is longer than a traditional battery.

1 of 1 people found this helpful.

You could test the output of the alternator to see if it is performing okay...Noise is the main concern...if it is worn out will be noisy~ 12.5- 15.0 volts is what the regulator should be putting out~

oops 13.5 to 17 volts running...my bad~~~

98,565

I had this happen to me with a thunderbird doing the same thing, alternator tested good until the RPM's came up then the brushes started what they call bouncing, it happens when the rotor contact rings become slightly egg shaped and cause the brushes to lose contact with the rings at higher speeds, replaced the alternator and the problem went away. You might also check your belt tensioner and serpentine belt for good measure as the tensioners are know failure items.

1 of 1 people found this helpful.
69,555

On newer vehicles the battery light will come on when the alternator is overcharging as well as when it's not charging at all. HTH. -Jim

1 of 1 people found this helpful.
113,325

Could your alternator belt be slipping some upon acceleration?

2 of 2 people found this helpful.

Your Answer

F-150

Looking for a Used F-150 in your area?

CarGurus has 181,253 nationwide F-150 listings starting at $1,000.

ZIP:

Ford F-150 Experts

  • #1
    OJ
    Reputation
    8,760
  • #2
    dandyoun
    Reputation
    4,490
  • #3
    tennisshoes
    Reputation
    3,010
View All

Related Models For Sale

Used Chevrolet Silverado 1500
2,166 Great Deals out of 181,094 listings starting at $1,900
Used GMC Sierra 1500
796 Great Deals out of 67,430 listings starting at $1,350
Used Dodge Ram 1500
402 Great Deals out of 10,724 listings starting at $1,500
Used Ford F-250 Super Duty
353 Great Deals out of 43,423 listings starting at $975
Used Toyota Tundra
446 Great Deals out of 33,526 listings starting at $1,999
Used Toyota Tacoma
578 Great Deals out of 41,954 listings starting at $2,995
Used Ford F-250
468 listings starting at $3,490
Used Ford Mustang
760 Great Deals out of 41,952 listings starting at $1,300
Used Chevrolet Tahoe
644 Great Deals out of 37,360 listings starting at $1,800
Used Ford Explorer
798 Great Deals out of 62,687 listings starting at $999
Used Ford F-350 Super Duty
349 Great Deals out of 23,406 listings starting at $2,990
Used Chevrolet Silverado 2500HD
316 Great Deals out of 29,243 listings starting at $2,650

Used Cars For Sale

2018 Ford F-150 For Sale
7,570 listings starting at $18,539
2017 Ford F-150 For Sale
74 Great Deals out of 105,445 listings starting at $15,407
2016 Ford F-150 For Sale
120 Great Deals out of 7,717 listings starting at $18,990
2015 Ford F-150 For Sale
273 Great Deals out of 9,917 listings starting at $15,890
2014 Ford F-150 For Sale
368 Great Deals out of 13,150 listings starting at $8,990

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.