820-3462 Amber light

Ryanlen2

Member
Hi, I have this board from another shop. It is very clean. Nothing visually wrong with it as of now. Dont think it even had liquid damage. Without battery green light turns amber after a couple seconds. I dont know much more as of yet. Im getting this in now in case you see this so I have an idea what to look for in the morning. I do know I have all G3H, PP3V42, PP18VDCIN, PPVRTC (16.5V) and PP5V_S5 & PP3V3_S5. I also know Im missing S4 power.Possible SMC issue most likely because of amber light? Thank you, have a good
night/day.


Update 1 - Missing PP5V-S4. Missing P5V_S4_EN.

U7970

pn 6 - 3.3V
pn 2 - Low (0V)
pn 1 - (SMC_S4_WAKESRC_EN) Missing.

SMC_S4_WAKESRC_EN Diode mode - .667
L4901 3.4V


Udate 2 -

Tried reflow on SMC. No change.
Reballed SMC - No Change.


Thanks.
 
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dukefawks

Administrator
Just messing around without diagnosing anything?

First measure PPBUS and PPVRTC and report exact values here. Also inspect the common corrosion points on these, U1900, U1950 pin 8, U6100 and termination resistors. Check for power cycling on 5V_S4 preferably with a scope.
 

2andrewd

New member
the charger light is amber while charging battery or lacking one entirely by design on these.

Edit*** therefore... The orange light is arbitrary.
 
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2andrewd

New member
Sorry. To clarify... Someone correct me if I'm wrong, but these models have an orange light present whether there is a battery installed or not. The only time the light will hold solid green is WITH a battery when fully charged. The orange light alone the way you're describing isn't enough indicate the smc.

BTW what is the problem you're experiencing here anyway,? they need to understand what it is you're aiming to solve.



Always deferred to the expert above- what voltages are present on the rails Duke requested.
 

Ryanlen2

Member
Yeah... I just like re-balling shit...

Honestly I thought since I was missing SMC_S4_WAKESRC_EN for P5V3V3_S4_EN that SMC would be possibility since thats where it comes from and i may as well try it. PPBUS is 12.56V and PPVRTC is fluctuates from 16.18 to 16.435V. I'm assuming you meant U2600 and U2650? U2600/50 both look good .99 to .107 on pin 8 U2650. No power cycling on P5V_S4. U6100 looks good. R5021 - 24Ohm, R5022 - 43Ohm, R5023 - 15Ohm R5024 - 15Ohm.
Thanks Duke.

2andrewd -
Thank you. I didnt know that the orange light stays on with or without battery. Problem I am experiencing is no power/fan spin. Missing P5V_S4.
 
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dukefawks

Administrator
If there really is 16v on PPVRTC this board is totally fried, check what you are measuring, should never be more than 3.4V.
 

Ryanlen2

Member
Your right. Sorry I miss typed. That was PPDC-IN Didnt eat today. Get back to you with that. Thanks have a good one.
 
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Ryanlen2

Member
PPBUSG3H - 12.56V
PP3V42 - 3.4V
PPVRTC is 3.33V
PPDCIN - fluctuates 16.18 to 16.43V
PP5V_S5 - 5V
PP5V_S4 - .001
PP5V_S3 - MISSING
PP3V3_S5 - 3.33V
PP3V3_S4 - 0.44
PP3V3_S3 - 0.004

PIN 8 U2650. I plug in the charger and take measurement. At first it climbs to 0.110V then slowly drains to around -0.015V then slowly start to climb again. Repeats this. How am I getting anything on 3V3_S3 without any other ones?

Thanks Duke. Have a good day.
 

2andrewd

New member
Let's see if we can get all s5 rails before looking into FireWire/ether net. The reading on s3 is negligible.

Voltage on pm_slp_s4_l ?
 

2andrewd

New member
Voltage drop to ground on pm_slp_s4_l in diode mode?

Voltage on smc_on_off_l?

u6100 termination resistors within spec? Traces between intact?
 

dukefawks

Administrator
I bet the machine is power cycling seeing the DCIN voltage is going up and down. Measure carefully on 5V_S4 preferably with a scope as a multimeter is too slow to catch the short pulses.
 

Ryanlen2

Member
Duke. I waited like 5 minutes on the PP5V_S4 with multi meter. stayed at .001. i dont have scope. If it is cycling and I cant catch it. Anything I can do. (besides buy a scope) :rolleyes:

Ill take your bet.
 
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Ryanlen2

Member
U1950, U1900? Do you mean something else? I dont have in boardview or schematic.


U2600, U2650?


​​​​​​​Thanks
 
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