1997 - 2003 F150 1997-2003 F150, 1997-1999 F250LD, 7700 & 2004 F150 Heritage

Headlights only work on high beam

Thread Tools
 
Search this Thread
 
  #1  
Old 07-15-2010, 11:19 PM
Budman1962's Avatar
Budman1962
Budman1962 is offline
Senior User
Thread Starter
Join Date: Mar 2007
Location: Montana
Posts: 440
Likes: 0
Received 0 Likes on 0 Posts
Headlights only work on high beam

I bought a 97 f150 stepside. I have been working on a few problems on the truck. One problem I can't figure out is the headlights. There is no power going to them on low beam. Is there a fuse or relay that could be out. I don't have an owners manual. Thanks
 
  #2  
Old 07-16-2010, 06:21 AM
93 mix 'n match's Avatar
93 mix 'n match
93 mix 'n match is offline
Posting Guru
Join Date: Mar 2009
Location: Montague, NJ
Posts: 1,845
Likes: 0
Received 0 Likes on 0 Posts
there is a relay. go to autozone and buy a haynes manual.
 
  #3  
Old 07-16-2010, 06:24 AM
Budman1962's Avatar
Budman1962
Budman1962 is offline
Senior User
Thread Starter
Join Date: Mar 2007
Location: Montana
Posts: 440
Likes: 0
Received 0 Likes on 0 Posts
Thanks for the reply. Is there a separate relay for high and low beam?
 
  #4  
Old 07-16-2010, 06:28 AM
93 mix 'n match's Avatar
93 mix 'n match
93 mix 'n match is offline
Posting Guru
Join Date: Mar 2009
Location: Montague, NJ
Posts: 1,845
Likes: 0
Received 0 Likes on 0 Posts
im not sure, but i think so. id go look but mines at the alignment shop.
 
  #5  
Old 07-16-2010, 09:36 AM
steve(ill)'s Avatar
steve(ill)
steve(ill) is offline
Hotshot
Join Date: Jul 2005
Posts: 11,807
Likes: 0
Received 115 Likes on 102 Posts
read page 209--- then download the book

http://www.motorcraftservice.com/pub.../02f12og4e.pdf
 
  #6  
Old 07-16-2010, 03:47 PM
projectSHO89's Avatar
projectSHO89
projectSHO89 is offline
Hotshot
Join Date: Jan 2004
Location: St Louis
Posts: 19,342
Likes: 0
Received 873 Likes on 725 Posts
Originally Posted by 93 mix 'n match
there is a relay. go to autozone and buy a haynes manual.
Uh, NO!. There is no relay in the low-beam (or high-beam) circuit on a 97.

The output of the MFS (Rd/Bk wire) splits to two separate fuses (under-dash F28 and F26) that individually protect the left and right low-beam headlamp circuit. There is nothing else in the circuit.

Check the output of the MFS at the two fuses.
 
  #7  
Old 07-16-2010, 11:12 PM
Budman1962's Avatar
Budman1962
Budman1962 is offline
Senior User
Thread Starter
Join Date: Mar 2007
Location: Montana
Posts: 440
Likes: 0
Received 0 Likes on 0 Posts
Thanks for the replies. I checked the fuses and they are ok. Tomorrow I will check the voltage at the fuses. If nothing there I will disassemble the MFS.
 
  #8  
Old 07-17-2010, 12:17 AM
mikesheldon's Avatar
mikesheldon
mikesheldon is offline
Freshman User
Join Date: Jul 2010
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
there is a chance that both headlight bulb filaments have gone on high beam, maybe one went a wile ago and you didnt notice, or it is your actaul switch
 
  #9  
Old 07-17-2010, 08:46 AM
projectSHO89's Avatar
projectSHO89
projectSHO89 is offline
Hotshot
Join Date: Jan 2004
Location: St Louis
Posts: 19,342
Likes: 0
Received 873 Likes on 725 Posts
Yep, there is a chance that both bulbs have gone. The voltage check at the two fuses will give him guidance on which half of the circuit has the fault.
 
  #10  
Old 07-17-2010, 11:08 AM
Budman1962's Avatar
Budman1962
Budman1962 is offline
Senior User
Thread Starter
Join Date: Mar 2007
Location: Montana
Posts: 440
Likes: 0
Received 0 Likes on 0 Posts
No power to ether fuse 26 or 28. I checked it with the head light switch on. I will open up the MFS next.
 
  #11  
Old 07-17-2010, 12:14 PM
Budman1962's Avatar
Budman1962
Budman1962 is offline
Senior User
Thread Starter
Join Date: Mar 2007
Location: Montana
Posts: 440
Likes: 0
Received 0 Likes on 0 Posts
Fixed !! I disassembled the MFS and cleaned all the contacts with a scotch brite pad and electronic cleaner. Then I put a thin coat of dielectric grease and resembled it. It is working great. Thanks everyone for the help.
Budman
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
mechasus
Escape & Escape Hybrid
12
10-25-2021 04:06 PM
DeadFife
1999 to 2016 Super Duty
10
04-28-2017 07:12 PM
DaMonsterMonster
1987 - 1996 F150 & Larger F-Series Trucks
6
11-29-2015 08:23 PM
44vulcan
1987 - 1996 F150 & Larger F-Series Trucks
14
11-27-2015 04:37 PM
Weezman
1978 - 1996 Big Bronco
4
09-09-2008 05:04 PM



Quick Reply: Headlights only work on high beam



All times are GMT -5. The time now is 03:51 AM.