HELP! LED problem

Discussion in 'The Projects Forum' started by e3silversurfer, Mar 25, 2010.

  1. e3silversurfer

    Thread Starter New Member

    Mar 25, 2010
    2
    0
    Hi there everyone, I am new here and well I came across this site whilst searching for some info regarding a SOT 89 package component.

    Ok, let me start from the beginning. I have have got this problem with the rear lights of my vehicle and decided to take it apart to see what the problem was. Before anyone suggests getting a replacement lamp module, I have been quoted £100 to replace it, which i think is over the top.

    Basically the symtoms of the lamp are as follows. there are 22 leds on the pcb. When the "taillight" function is on, 2 of the leds do not power on but when then "brake" function is on, all leds are on.

    this system uses a off, dim and bright function to operate the OFF, Tail lights and Brake lights function.

    [​IMG]

    on this image, LD11 and LD12 do not turn on when the Tail light Function is on.

    there are 3 chips on the pcd

    1) Precision Adjustable Shunt Regulator

    [​IMG]

    2) Postive Voltage Regulator

    [​IMG]

    3) UNKNOWN (markings on the case is NA2... thats all :( )

    [​IMG]





    Does anyone know what the last chip is? would like to hear any ideas and opinion on how to get this repaired. Thank you all very very much :)
     
  2. R!f@@

    AAC Fanatic!

    Apr 2, 2009
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    760
    it can be done but it won't be easy
     
  3. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    8,754
    760
    see whether you can clear out the glue and debris so we can take a clear look at the circuit layout
     
  4. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    8,754
    760
    Or is it possible to measure the voltage as in the pic
     
    • Tail.jpg
      Tail.jpg
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  5. e3silversurfer

    Thread Starter New Member

    Mar 25, 2010
    2
    0
    hey thanks for the quick response. what i am doing currently is probing the entire pcb to get a schematic drawing. I will be connecting the unit back onto the car to get a voltage reading from there when i get home tonight.
     
  6. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    8,754
    760
    OK..tht'll help
     
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