I have noticed that my headlights pulse bright, dim, bright, dim....Why???

Is my alternator going bad? This is generally the first 45 minutes and i have no other issues anywhere. I have an 04 6.0 diesel.

Ideas? I have heard of an alternator wiring upgrade, anymore info?

THANX EVERYBODY!!

 

Yes, the alternator and or regulator is going bad.

 

..or you have a high resistance in the battery voltage monitor circuit back to the alternator. That was a very common on Ford's Contour and Cougars. Caused the entire lighting circuit to go dim..bright..dim...bright..., etc several times per second. The fix on those vehicles is to modify the wiring harness.

 

Mine was doing this one time and i found that the wiring harness plug going into the top of the alternator had backed out just enough and was causing my light to go dim and bright like pulsing. Pushed the plug back down into the alternator and problem fixed. May be something to check but i hear alternator go out often on the EX. Maybe worth a try?

 

I just replaced my alternator (for the 3rd+ time) because of this. If you take it out and bring it in to get tested, it might not test "Bad". It is most likely the Voltage Regulator going out. The next thing you see will be the Battery light flickering on and off (if you're lucky). I got a nice replacement alternator (High Amp/Heavy Duty) from:

http://store.alternatorparts.com/6g-...lternator.aspx

I went through 2 NAPA Alternators within a year, so I wouldn't suggest those. The National Quick Start one lasted me about 60,000 miles and just went out two weeks ago (left me stranded at a gas station; no flickering, but lights were dim). A lot of people suggest just going with a Motorcraft from the Dealer or Parts Guy Ed; that alternator lasted over 100,000 so it can't be that bad.

 

I just replaced my alternator (for the 3rd+ time) because of this. If you take it out and bring it in to get tested, it might not test "Bad". It is most likely the Voltage Regulator going out. The next thing you see will be the Battery light flickering on and off (if you're lucky). I got a nice replacement alternator (High Amp/Heavy Duty) from:

http://store.alternatorparts.com/6g-...lternator.aspx

I went through 2 NAPA Alternators within a year, so I wouldn't suggest those. The National Quick Start one lasted me about 60,000 miles and just went out two weeks ago (left me stranded at a gas station; no flickering, but lights were dim). A lot of people suggest just going with a Motorcraft from the Dealer or Parts Guy Ed; that alternator lasted over 100,000 so it can't be that bad.

 

projectsho89, You wouldn't happen to know how they modified the wiring harness for the fix? I am currently seeing this same scenario in a Ford division vehicle.