Macbook Air 000165 No P5VS4RS3_EN_L

[BrickBreaker]

Light on charger no fan spin.
PP3V42_G3H - 3.430V (pin 1 R7095)
PPBUS_G3H - 8.59V (pin 2 F7140)
PP3V3_S5 - 3.324V (pin 2 L7560)
PP5V_S5 - 0.0V (pin 1 L7520)

PP3v3_SUS - 3.323 (pin 8 U6100)
PVRTC_G3H - 3.324 (pin 1 U1900)
P5VS4RS3_EN_R - 0.0V (pin 1 R7551)

I changed U1900. No visible damage. The case has some liquid but board is clean. Liquid is all along the lcd hinge black plastic bar. RTC chip U1900 is common. Maybe I try touching up that job.

[piernov]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

Resistance to ground of PP5V_S5?

[BrickBreaker]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

Oh and the client said that it "just turned off unexpectedly" and wouldn't turn back on.

[BrickBreaker]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

Resistance to ground of PP5V_S5?

35.0 kOhm
0.457 V Diode mode

[piernov]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

Uhm… L7520 is PP5V_S4RS3, not PP5V_S5. PP5V_S5 is the LDO (VREG5) output of U7501.
I guess PP5V_S5 is present and PP5V_S4RS3 is missing due to missing PM_SLP_S4_L.
Check if the rails are pulsing or not. Check the usual RTCRST#, SRTCRST#, DSWVRMEN, DPWROK, SLP_SUS#, INTVRMEN, RSMRST#, PWRBTN# of the PCH. Check the SPI ROM traces and resistor. You said you replaced U1900 so I guess it's ok.
Really no liquid damage on the board? There should be something somewhere and it would help us a lot.

[BrickBreaker]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

O shiz you're right. I thought I measured again on the other side, C7505 right next to U7501. Oops, well that's my bad.
You are right and PP5V_S5 is there at C7505. As far as pulsing, my multimeter is reading a steady voltage on all the power rails (3v42, ppbus, 3v3, 5v). Thanks for all the suggestions, I am going to try and find all those usual suspects and give readings.
In meantime here is what I found. MOSI and MISO are not "talking." I have been told to look for this. I am referring to U6100 pins 2 and 5. Steady 3.319V on both. Also, PCH_CLK32K_RTCX1 is measuring .423V and I am told that it should be about 0.8V.

[piernov]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

Sorry I was asking if the "next" power rails are pulsing, the ones you're missing, and PM_SLP_S4_L too.
MOSI and MISO are very high speed communication lines, if you don't have a high-bandwith oscilloscope (100Mhz at least IIRC) you may not catch it. CS# pin is easier to measure and will also tell you if there is activity. If the power lines are not pulsing and if the traces and resistors of the SPI ROM look good the issue shouldn't be there. (BIOS can get corrupt but that's unlikely here)

I'm not sure about the exact voltage of PCH_CLK32K_RTCX1 (may not show up the same on different multimeters as well), but if you replaced U1900 and you have PPVRTC_G3H, it should be ok. If still in doubt, replace it again and check the pads and traces.

[BrickBreaker]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

Next as in S4?
I meant to mention that I don't have a oscilloscope. I checked continuity along the traces for SPI ROM. I replaced U1900 twice already, first time with a new chip (from china of course) second time from parts board just in case stock was bad. Here were my readings.
RTCRST#, 3.318V
SRTCRST#, 3.318V
DSWVRMEN, 3.228V
DPWROK, 3.433V
SLP_SUS#, 3.323V
INTVRMEN, 3.229V
RSMRST#, 3.294V
PWRBTN# 3.427V

[piernov]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

Ok so everything is fine there.
Voltage on SMC_ADAPTER_EN and PM_BATLOW_L?
Make sure you really don't get any spike on PP5V_S4RS3.

[BrickBreaker]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

SMC_ADAPTER_EN - 3.431V
PM_BATLOW_L - 0.035V
PP5V_S4RS3 is flat 0.0 no spike.

[piernov]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

Plug in a known good battery and check again.

[BrickBreaker]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

Plugged in battery, got fan spin. I saw definite corrosion under SMC on Tuesday so I did a reball on SMC just now. After that, I get fan spin and cpu gets warm if I have a battery attached. On magsafe only I get the same as before, light on charger, no 5v no fan obviously. So now I know where to look, gonna maybe check that I get chime and stuff with battery. My thinking for the magsafe only problem is batt current sensing, ISL talking to SMC... Yea I'll update.

[piernov]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

Check if it boots fully with battery. If it does, don't forget to check if fan spins normally and that HWSensors report correct values. You're probably set and the computer is working properly.

About the AC adapter only issue, your Magsafe might not be recognized properly. Those boards are very picky about the Magsafe. Use an original Magsafe 2 60W. Don't try to dig further into a board issue before trying another known good Magsafe, and check if battery charges properly inside the computer.

[BrickBreaker]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

Bigups thanks for that. I will definitely boot it first and check out those things. For the magsafe only issue, the connector J7000 has PP5V_S4RS3 on pin 3. This is 5.1V without* the io cable plugged in. The fan spins as soon as i connect the charger too, if the io cable is not there. With the io cable = 0V on pin 3. Also if the Battery is attached, I can get 5.1V on pin 3 of J7000 even with the io cable attached.

[piernov]

Re: Macbook Air 000165 No P5VS4RS3_EN_L

That's definitely an issue with the Magsafe. Some Magsafe aren't recognized properly with this board. On the other hand, if the computer runs fine and the battery charges correctly, don't bother to dig into this issue.