Flickering Headlights / Lights - SOLVED

[ZBrink]

I have a 2000 GMC Yukon XL 1500. Like many, I was plagued with all my lights flickering or pulsating at seemingly random times (headlights, dash lights, interior lights, etc). The flickering was ever so slight making you question your sanity as if it was even actually happening. Those who have experienced this know exactly what I'm talking about! Ha! I scoured the web for a solution and it seemed that guys would replace their alternator and the problem would go away. This was unacceptable to me as my battery is old and was getting charged just fine by my alternator so I knew the alternator was at least partially functioning.

 

The real problem as it turns out was the voltage regulator inside the alternator as the factory ones are weak. This was an easy and inexpensive fix. Taditel and Transpo both make redesigned heavy duty voltage regulators for the factory AD244 130 amp alternator for under $20. These are better regulators than factory and better than the ones installed on new, rebuilt or remanufacturered alternators (unless purchased from a performance shop). The new regulators have a different appearance but fit as factory.

 

The alternator itself is very easy to remove from the truck and the back of it is plastic comes off with the simple prying of a screwdriver. There are some YouTube videos showing you how to rebuild this exact alternator which you can watch just to see how they remove and reinstall the regulator. You need an E5 Torx socket and a small soldering gun with accessories to remove and reinstall the new and better regulator. You can also replace the brushes while you're in there as it only requires a screwdriver and the brushes are about $5. The whole process including removal and reinstalling of the alternator, took about 1.5 hours and cost less than $20. A high quality remanufacturered alternator was around $75 + core charge and it would have come with the same old style voltage regulator which would eventually burn out before the alternator itself.

 

Problem solved! No more flickering or pulsating lights! Wahoo!

Edited December 19, 2016 by ZBrink

[TAZ DEVIL]

Thanx ZB, I've had (and have) a lot of GM trucks that have the slight twinkle in their eyes. Always figured just one of those things.

Good info !

[BowTieChevy]

Thank you fir this info as I have same issue since replacing 145 amp alternator with an AC Delco remanufactured alternator.  In forums, I too learned it was the voltage regulator.  I removed alternator and scrubbed all points of contact to alternator mounting flanges and mounting bracket and it stopped temporarily.

 

Please, will you provide me with the contact info for both Taditel and Transpo so I may get the right regulator for my 145 amp alternator?

 

Thank you very much!

[davester]

what truck do you have?  If it's a more recent (around 2000 or newer), the trucks computer controls how the alternator works.