i had repair come in, client spilled coffee on 2008 macbook pro a1281. doa, ordered new logic board our buddies @ blue raven. installed new board (apn 661-4835) , has failed solve issue.
mbp not start @ all, no chime, no hd noise, nothing. magsafe shows green light, , battery charged.
things have tried:
pram reset
smc reset
swapped memory
replaced dc-in
different magsafe
cursory examination of logic board physical defects
@ point, i'm 99% sure it's hardware related issue, since whole things pretty doused in coffee when came in. thinking battery cable, don't know that affect startup attempts bypass battery, using magsafe. if it's not power issue, thinking ram, neither set of sticks i've tried has worked. a1281 had several iterations, each own logic board. there slight possibility original board pulled 661-4834, identical 4835 exception of more vram , 2.53 ghz chip rather 2.4. don't think should make difference, , i'm pretty sure original 4835, i'm disinclined think that's problem. i'd think new board wasn't doa blue raven, , i'm confident enough in skills didn't damage new board during installation, barring possible logic board faults, have idea causing no-boot situation such this? appreciated!
there more wrong...
there more wrong board. repair liquid spilled boards living , i've seen million times. in order these boards start up, must right. if replacement logic board indeed good, else connected causing not start.
causes are:
1) computer told start when standby voltage generated power manager grounded. keyboard shorted internally liquid , power button being held down (electrically) or in other way shorted , causing not start.
2) lvds cable/display module shorted , causing not start.
3) airport/bluetooth connector/cable shorted.
4) combination of factors.
can try diagnose:
1) disconnect lvds cable , try starting keyboard power button. leave lvds cable disconnected.
2) disconnect airport/bluetooth/camera cable , try starting keyboard power button. leave airport cable disconnected.
3) disconnect rest of peripherals: hard drive, optical drive , track pad.
4) disconnect keyboard , try starting momentarily shorting pin 5 on keyboard connector ground. unit should turn on.
if have meter, check pin 5 of keyboard connector. should read ~3.38 volts power manager magsafe plugged in , light green. if reads zero, keyboard bad (the power button shorted).
can test blue raven board on bench, not installed in unit. connect known-good magsafe connector , fan. should see green light on magsafe adapter. means power manager running (and has turned light green). if short pin 5 of keyboard connector ground, unit should start (fan should turn on). if not, logic board 100% bad. don't run more few seconds without heat sink installed. long enough see turn on.
can give further troubleshooting steps - feel free contact me @ email: joe@microreplay.com.
way, 1 of original founders of pre-owned electronics, 6 years ago became blue raven. no longer affiliated them in anyway (i sold out 6 years ago before current management team came in).
let me know if can help.
joseph kouyoumjian
www.microreplay.com
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