Search results

Checked all resistors on page 61 "SPI Bus Series Termination". J6100 always gets removed and the pads wicked cleaned. I'll recheck monday again maybe I missed one. I think originally the only visible signs of liquid damage were at j6100.

No Title Here ya go. "Hi-Res"... from the crappy amscope camera. I just need to buy the canon slr adapter. I checked and double check all of the lines back to the resistors under the CPU. 3.3v getting to all of the pins on the bios chip that need it. U1900 getting all of the proper power as well.

Yes, 0-.5v in two second intervals.

Changed the bios chip w/ a known good one. No change in state at all. Maybe time to throw this one in the bin?

u1950 getting 3.42 volts. All termination resistors test as ok (none failed high resistance anyways) and the traces connect thru on each end. No issues with pads / traces at u1900, chip is getting power. I will probably replace u6100 with a known working one and see what happens.

So.. pp3v3_s5 and pp5v_s5 are present. s5_pwrgd = 3.42 pm_dsw_pwg = 3.42 pm_slp_s4_l is fluctuating between 0 and 2 volts every couple of seconds. s4 rails are cycling voltage similarly as well.

Getting all g3hot rails. Not getting any s4 rails. ALL_SYS_PWRGOOD cycles between ~.5V and 0V. Any ideas? Thanks, Stefan

Close please! CAMERA_PWR_EN was missing. R2030 zero ohm link was burned and needed replaced.

LB is in S0 state. PP3V3S0 present. U3900 not producing PP1V2_CAM, PP1V8_CAM, or PP1V35_CAM. No other issues, just onboard camera does not power on. CAM_DEBUG_RESET_L is 0. Slightly confused, it is U3900 that produces PP1V8_CAM, correct? Thanks, Stefan

If I touch it and it alters state, I try to rip it all off an replace it if possible... No one likes you when their machine works intermittently.

I just had a 2016 mpb in with liquid damage. I took 3 weeks to work on it, only pulling it out and working it when I had a clear head. Rest of the time, head down, get other repairs done that aren't as mentally taxing, and make sure you have time to relax. If a customer absolutely needs a...

There is really no way around time consuming... you either rip it out or individually remove each rivet holding it in.

Did the BIOS chip have a clean ME region?

Found one.

FIXED! All repairs listed: Replaced passives around U3200. Lots of ruined caps and resistors. Ran wire to reconnect pins 19, 21, on the DFR Touch Connector. Fan control at Q6050 was screwed up. Had to replace R6051 and run wire to reconnect it to pp3v3_s0. My first time with a touchbar mac...

Board is on my low priority queue at the moment. Switched fans and same behavior. Ridiculous but there is fan control circuitry on the back of the keyboard. The keyboard ssembly is a PCB substrate. I see no signs of corrosion on it however. Standard behavior is no fan spin I believe. With tpad...

I solder a bridge at the base of the hd temp connector on the main logic board. Note that you must be careful to not drop excess solder across the board anywhere. This only works if you want the fans to spin at low speed all of the time. If you want them to spin faster you must use a fan...

Hello, I got a new one in the shop today. Left side liquid damage. Replaced tons of ruined passives around U3200. Board would not get power from USB C charger before, now it gets power, charges, and boots. I had to reconnect pins 19 and 21 on the J4402 "DFR Touch Connector" due to corrosion...

Any iMac with the separate cable, whether it has a temp sensor or a plug for the HD can be safely bridged. The SMC will just read the HD temp as 0 degrees and keep the fan at normal speed.

Check the bridge cable for corrosion as well. I often see corrosion on that pin shorting the line out. Try a new cable.