why are my lights dimming

Asked by suchster36 Feb 13, 2015 at 11:52 AM about the 2004 Ford F-150 XLT Ext. Cab 4WD

Question type: Maintenance & Repair

when im driving the lights an heater dim when I come to a stop or take my foot off the brake, replaced the alternator an battery an still does it

4 Answers

74,270

Dimming lights are an indication the proper voltage is not being applied to the circuit. Remove the fuse associated with the lights. Use a digital volt meter and check for 12 volts across the two terminals. You may have a loose or corroded ground. Check the ground from the battery to the block and make sure it is not corroded. Also check the alternator with the engine running. It should read slightly over 14 volts. Rebuilt alternators have been known to be bad out of the box.

6 people found this helpful.

I HAVE A 2001 F150 I REPLACED THE STARTER AND ALTERATOR AND BATTERY MY LIGHTS FLUX TO THE ENGINE BRIGHT AND DIM

157,625

This thread is 9 years old. Please start a new thread so everyone can see your question. Jim

Your Answer:

F-150

Looking for a Used F-150 in your area?

CarGurus has 14,968 nationwide F-150 listings starting at $1,712.

Postal Code:

CarGurus Experts

  • #1
    OJ
    Reputation
    42,520
  • #2
    Gene Arnett
    Reputation
    16,040
  • #3
    Rowefast
    Reputation
    15,860
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Chevrolet Silverado 1500
202 Great Deals out of 5,975 listings starting at $2,975
Used GMC Sierra 1500
148 Great Deals out of 7,258 listings starting at $3,950
Used Ford F-250 Super Duty
24 Great Deals out of 1,204 listings starting at $7,995
Used Toyota Tundra
35 Great Deals out of 1,184 listings starting at $8,500
Used Toyota Tacoma
55 Great Deals out of 1,071 listings starting at $8,708
Used Dodge RAM 1500
3 Great Deals out of 71 listings starting at $4,000
Used Ford Ranger
18 Great Deals out of 1,529 listings starting at $2,888
Used Ford Mustang
65 Great Deals out of 1,259 listings starting at $4,995
Used Chevrolet Silverado 2500HD
16 Great Deals out of 1,285 listings starting at $8,995
Used GMC Sierra 2500HD
17 Great Deals out of 1,640 listings starting at $9,988
Used Ford F-350 Super Duty
39 Great Deals out of 2,598 listings starting at $8,888
Used Ford Explorer
86 Great Deals out of 2,065 listings starting at $2,999

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. Content will be removed if CarGurus becomes aware that it violates our policies.