FSC - Chevy Truck Forum

Thread: LED bulb replacement and hyper flashing - a DIY solution

Page 1 of 5 123 ... LastLast
Results 1 to 20 of 93
  1. #1
    Registered User 01 Suburban LS's Avatar
    Join Date
    Sep 2003
    Location
    San Jose, CA
    Age
    45
    Posts
    476
    My Feedback

    (0% Positive Feedback)

    LED bulb replacement and hyper flashing - a DIY solution

    I did a quick search to see if this info was posted before, nothing came up so here I go:

    I recently replaced all the bulbs in my 2001 Suburban with LED replacements from hid-lights.com. Specifically the ones that I'll post a pic to below. Anyway, I figured I'd have a problem with hyper flashing. After a little searching on-line a DIY solution was found.

    Inside our flasher is a chip. It is a U643B Automotive Flasher chip. It basically controls the relay that turns the lights on and off. This chip has circuitry that can detect when a light is out by looking for a reduction in load (current). The chip will see this and trigger the lights on and off twice as fast to alert the driver that a bulb is out. From what I can find out by researching the flashers part number, 1999-2002's use the same flasher as my 2001. But I have owned other GM vehicles with a different flasher modules that this same mod works on. If you open up the flasher module and the U643B chip is present, this mod should work for you.

    Luckilly this is all done with one pin on the chip. What you need to do is take the stock electronic flasher apart and cut the leg of the chip on pin 7 coming off the chip. You will loose the 'lamp failure detection' on the chip. But the lights will flash normally. And you saved some money as long as you don't break the flasher.

    Click the link below for more information on the U643B chip.
    http://www.atmel.com/dyn/resources/p...ts/doc4727.pdf




    Here's my DRL's replaced with LED bulbs.
    Last edited by 01 Suburban LS; 05-06-2011 at 10:36 AM.
    2001 Suburban LS.
    18x10 Eagle 064's, 6" ProComp lift, Ford Keys, 1.5" rear coil spacers, 35x12.5x18 ProComp X-Terrains

    http://www.cardomain.com/ride/2175737


  2. #2
    SPL NUT!!! idbl_Fanatic's Avatar
    Join Date
    Jul 2002
    Location
    Stockton, Ca
    Age
    44
    Posts
    1,838
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    Can you post a pic of the inside of the flasher? so that people will know what "leg" to cut?


    Need more power? UP YOURS!! with Excessive Amperage!

  3. #3
    Registered User 01 Suburban LS's Avatar
    Join Date
    Sep 2003
    Location
    San Jose, CA
    Age
    45
    Posts
    476
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    I'll will when I do the one on my parents Tahoe. But if you download the PDF from the link above you'll see a drawing of the chip. Its very self explanitory.
    2001 Suburban LS.
    18x10 Eagle 064's, 6" ProComp lift, Ford Keys, 1.5" rear coil spacers, 35x12.5x18 ProComp X-Terrains

    http://www.cardomain.com/ride/2175737


  4. #4
    most unique username
    Join Date
    Oct 2001
    Location
    Bainbridge, NY
    Age
    42
    Posts
    8,577
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    Nice find! Thats good info - sometimes its hard to find detailed tech info on chips/modules used in the automotive world.

    So you've actually done this and things work fine? Just curious because after reviewing the info I was thinking that without proper input to pin 7, the comparator (K1) would go high, driving the pulse generator into double rate mode (just as if a bulb was out).

  5. #5
    Registered User
    Join Date
    Sep 2002
    Location
    Michigan
    Posts
    354
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    Can you tell if it is possible to access the resistor which controls the threshold of voltage that determines a bulb is out? If you replaced the 30 milliohm resistor with a different resistor, could you change the voltage at which the circuit thinks a bulb is out? (I just don't know where they come up with that 81 mV reference voltage.)

  6. #6
    Registered User 01 Suburban LS's Avatar
    Join Date
    Sep 2003
    Location
    San Jose, CA
    Age
    45
    Posts
    476
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    Quote Originally Posted by ibthumpin
    Nice find! Thats good info - sometimes its hard to find detailed tech info on chips/modules used in the automotive world.

    So you've actually done this and things work fine? Just curious because after reviewing the info I was thinking that without proper input to pin 7, the comparator (K1) would go high, driving the pulse generator into double rate mode (just as if a bulb was out).

    Yeah it works great. It may blink slightly faster than normal, but barely. Its definatly not flashing double time.

    I have some video taken with my cell phone. Unfortunatly you need the latest version of Quicktime to view the type of files my phone records. I'll post them below.

    http://www.differentracing.com/mike/...0Flash%201.3g2

    http://www.differentracing.com/mike/...0Flash%202.3g2

    http://www.differentracing.com/mike/...0Flash%203.3g2

    http://www.differentracing.com/mike/...0Flash%204.3g2

    Quote Originally Posted by MIZ71
    Can you tell if it is possible to access the resistor which controls the threshold of voltage that determines a bulb is out? If you replaced the 30 milliohm resistor with a different resistor, could you change the voltage at which the circuit thinks a bulb is out? (I just don't know where they come up with that 81 mV reference voltage.)
    I'll have to check, I honestly dont remember seeing it. But then again, I wasn't looking for anything but the chip.
    2001 Suburban LS.
    18x10 Eagle 064's, 6" ProComp lift, Ford Keys, 1.5" rear coil spacers, 35x12.5x18 ProComp X-Terrains

    http://www.cardomain.com/ride/2175737


  7. #7
    Registered User 01 Suburban LS's Avatar
    Join Date
    Sep 2003
    Location
    San Jose, CA
    Age
    45
    Posts
    476
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    As promised.

    Here is the high resolution image (1.9megs):

    http://www.differentracing.com/mike/...flasher-hi.jpg

    And the low resolution image (65k):
    http://www.differentracing.com/mike/...flasher-lo.jpg

    I labeled the pins on the chip. We just desoldered the leg of the chip, but if you have some fine tipped wire cutters, that should work too.
    2001 Suburban LS.
    18x10 Eagle 064's, 6" ProComp lift, Ford Keys, 1.5" rear coil spacers, 35x12.5x18 ProComp X-Terrains

    http://www.cardomain.com/ride/2175737


  8. #8
    Kick Ass!! Red94Chev's Avatar
    Join Date
    Sep 2005
    Location
    Edmonton, AB
    Age
    41
    Posts
    1,042
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    Are they quite a bit brighter than stock?

  9. #9
    Registered User 01 Suburban LS's Avatar
    Join Date
    Sep 2003
    Location
    San Jose, CA
    Age
    45
    Posts
    476
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    Quote Originally Posted by Red94Chev
    Are they quite a bit brighter than stock?
    They're about the same. Up front with clear corners the color is more intense. The instant on and off when flashing is pretty cool looking too. Orginally I was only going to do the DRL's since they always seem to burn out and the plastic socket was all burnt up.


    Incadescent Bulb:


    LED Bulb:
    Last edited by 01 Suburban LS; 03-26-2006 at 06:12 PM.
    2001 Suburban LS.
    18x10 Eagle 064's, 6" ProComp lift, Ford Keys, 1.5" rear coil spacers, 35x12.5x18 ProComp X-Terrains

    http://www.cardomain.com/ride/2175737


  10. #10
    Registered User 01 Suburban LS's Avatar
    Join Date
    Sep 2003
    Location
    San Jose, CA
    Age
    45
    Posts
    476
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    We also installed the same bulbs in my brothers Saturn SL2. Heres pics of his.


    Brake Lights:


    Turn Signal:


    Backup Lamp:
    Last edited by 01 Suburban LS; 03-26-2006 at 06:15 PM.
    2001 Suburban LS.
    18x10 Eagle 064's, 6" ProComp lift, Ford Keys, 1.5" rear coil spacers, 35x12.5x18 ProComp X-Terrains

    http://www.cardomain.com/ride/2175737


  11. #11
    Lost before Dawn CustomChevyGuy's Avatar
    Join Date
    Aug 2004
    Location
    305, South Fla
    Posts
    2,662
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    i realize this is an old thread, but would the same information apply to my 03 silverado? and if it does, where do i find the GM Combination flasher? up under the dash, or is it in the engine bay??

    thanks..
    Quote Originally Posted by bhookxen
    sometimes bad-assery takes time

    71 Chevelle 454
    03 rcsb, 06 clip/tails, HD hood, Esky handles, Alpine head unit, 5% tint, clear corners, 8K HID's, FM50, 2" rear drop, debadged, BlackBear Tuned!

  12. #12
    Registered User The Performer's Avatar
    Join Date
    Oct 2008
    Location
    Texas
    Age
    26
    Posts
    181
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    This is a good thread!

    I bet its in the under the hood fuse block. And I bet we have them in our 03's as well.
    Click to see my build!
    Proud DC owner!!!!

  13. #13
    S/C Z71
    Guest

    Re: LED bulb replacement and hyper flashing - a DIY solution

    :hack: Do it right and get the proper flasher.

  14. #14
    allergic to mud RollingBowTie01's Avatar
    Join Date
    Jan 2006
    Location
    North Bay, CA.
    Posts
    466
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    where is the flasher located under the dash?? i popped my head down there and came up with nothing.
    sig by 454ss
    01 silverado/4.8 jet chip/K&N 77 series/throttle body spacer/3/4 belltech drop/20x9.5 boyds wrapped in 295/45/20 Toyos/'05 tails/leds/and more to come.

  15. #15
    S/C Z71
    Guest

    Re: LED bulb replacement and hyper flashing - a DIY solution

    Turn your flasher on and follow the ticking sound.
    Last edited by S/C Z71; 03-05-2009 at 04:09 PM.

  16. #16
    allergic to mud RollingBowTie01's Avatar
    Join Date
    Jan 2006
    Location
    North Bay, CA.
    Posts
    466
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    i just went to the parts store and picked up an LED flasher. worked out way better then cutting anything.
    sig by 454ss
    01 silverado/4.8 jet chip/K&N 77 series/throttle body spacer/3/4 belltech drop/20x9.5 boyds wrapped in 295/45/20 Toyos/'05 tails/leds/and more to come.

  17. #17
    Registered User 01 Suburban LS's Avatar
    Join Date
    Sep 2003
    Location
    San Jose, CA
    Age
    45
    Posts
    476
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    Quote Originally Posted by RollingBowTie01
    i just went to the parts store and picked up an LED flasher. worked out way better then cutting anything.
    Except for the fact you did half the work by simply removing the old one and installing the new one.
    2001 Suburban LS.
    18x10 Eagle 064's, 6" ProComp lift, Ford Keys, 1.5" rear coil spacers, 35x12.5x18 ProComp X-Terrains

    http://www.cardomain.com/ride/2175737


  18. #18
    allergic to mud RollingBowTie01's Avatar
    Join Date
    Jan 2006
    Location
    North Bay, CA.
    Posts
    466
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    oh yea... damn the hard work that was pullin out the old one and pushin in a new one.. whew....
    sig by 454ss
    01 silverado/4.8 jet chip/K&N 77 series/throttle body spacer/3/4 belltech drop/20x9.5 boyds wrapped in 295/45/20 Toyos/'05 tails/leds/and more to come.

  19. #19
    ......................... Atomic's Avatar
    Join Date
    Jun 2005
    Location
    AL
    Age
    27
    Posts
    6,281
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    Where did you get a new one? Only ones I could find were $100+

    I got the $10 resistors from vleds instead.

  20. #20
    Registered User 01 Suburban LS's Avatar
    Join Date
    Sep 2003
    Location
    San Jose, CA
    Age
    45
    Posts
    476
    My Feedback

    (0% Positive Feedback)

    Re: LED bulb replacement and hyper flashing - a DIY solution

    Quote Originally Posted by RollingBowTie01
    oh yea... damn the hard work that was pullin out the old one and pushin in a new one.. whew....
    You missed my point. In the time it took you to stand in line to pay for that flasher. You can have done to the flasher you already have exactly what some Chinese kid being paid $0.10 a week did to the one you bought.

    Looking at your sig picture of your truck, I assume you did most if not all of that stuff yourself. Moding the flasher ranks up there in difficulty with swapping in those clear corner housings.
    Last edited by 01 Suburban LS; 03-29-2009 at 08:40 AM.
    2001 Suburban LS.
    18x10 Eagle 064's, 6" ProComp lift, Ford Keys, 1.5" rear coil spacers, 35x12.5x18 ProComp X-Terrains

    http://www.cardomain.com/ride/2175737


Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •