LG DVD player NO-DISC Complaint now revealed

Hi Friends,

 Wel-come to the wealth of knowledge Electronic repair articles

Today let me reveal how i repaired LG DVD  player NO-DISC  Complaint.
Before coming to this topic i would like to put word on this NO-DISC/DISC ERROR.

NO-DISC  Complaint is quite common in almost DVD.Many repair guide or Technical documents says the solution to change the lens assembly or adjust the spindle pan height,motor,Filter caps related to motor driver sections  etc.
Really its very headache job.Some of the DVD I was not able to solve doing all the above activities. Many time i am asking myself then what could be a problem?
Even i wasted a lot of time and money  by simply changing the driver ics  .After this i was not happy since i failed to solve the NO-DISC Complaint completely.Many mails and phone calls communicated with an experts but no use they are giving same solution what i said above.
Eighty percent of the complaint solves when we follow above steps but some of them will fail But,my concern what is the hidden secrete apart from that to solve no disc complaint 100% below is the story.

                                                ONE CAME FOR REPAIR
One of my friend brought the LG DVD Having complaint NO-Disc error. Since its a known story i was not so confident that i can solve this 100%. As usual checked lens assembly's servo activity found ok.Cleaned the lens,checked the spindle pan height found ok.Checked all the electrolyte capacitors carrying voltages and signals to Disk mechanism but no use. 

But this is the most challenging task for me.Once if i solve this i will get an answer & can realize the secrete beyond this.Next i wanted to conform weather the fault is in PCB's side or loader assembly side.For my goodness i got same model LG DVD in working condition.Below are the points i made repair activity Using this working DVD.

1)First  Exchanged the disc machenisum worked excellent & happy to see this and  conformed no issue with in the PCB side.

2) Now swapped the Lens from working to non working   NO Result same disc error

3) Checked and compared the spindle/servo  Motor resistance on both DVD  found within the spec(ie 5ohms to 20 ohms)

                                                       Motor tested from faulty  machenisum

                                                     Motor tested from good  machenisum


Again confused  me when  the lens/motor showing ok  on both DVD then what is making disc error inside the machnisum.Any how i lost confident & made my mind to give up and about to reassemble.Finally i got a small clue to run the motor with my dc source.So i tuned to 5volts turned on & compared both motor current drawn status to my surprise i got huge difference in current consumption.Alas that's what i required.Now again i got confident to fix this.

 DEFECTIVE SPINDLE MOTOR DRAWING HUGE CURRENT WHEN CHECKED IN DC SOURCE

Defective spindle motor drawing more then 1ampers   @ 5volts as shown.If this is the case then how this driver ic SA5888 will supply such huge current .By looking this i got  huge clue as a secrete and got confident i can solve this.Replaced the good spindle motor(<300milli-amps current drawn) and checked.DVD Worked excellent i felt very happy to see this,hope you all enjoyed this article .Happy reading let us meet in next class take care.

Best regards 
Basavaraj:BM 
basavarajradiotech @gmail. Com