Macbook A1466 2015 Version Battery was Drop Down Very Fast

Carte mère n° : 820-00165-A

Phénomène de dysfonctionnement :

Macbook A1466 2015 Version Battery was drop down Very Fast after it shows apple logo when disconnected with power supply by cable, but it was normal when use battery with power supply with cable together.

Raisons possibles :

1. Battery was broken;

2. Battery supply circuit or battery detective circuit on the motherboard was broken.

Dépannage :

We removed the back cover, replaced another battery and turned on the macbook, the malfunction was still the same, it means the problem was from the motherboard. We continued to take out the motherboard and check if there is any obvious corrossion or other damaged area.

After we checked, we found that there was an obvious water damaged area at the back side of the motherboard.

We opened the bitmap and schematic, and found out the corrosion area. It was around the SMC crystal circuit after we checked.

We connected with battery without power cable, and checked pin 1 of crystal Y5110 with oscilloscope.

The clock signal was generated when we powered on the macbook, but it was disappeared very fast when it showed apple logo, maybe that’s the reason why the battery was drop down very fast.

We removed the corroded components, and we found the pcb layer was broken under the crystal, then we used solder mask to cover there and replaced the corroded components R5110, Y5110, C5110, C5111.

After that we assembled all parts and connected with battery to test. All functions were back to normal.

Résumé :

The components on main clock signal line of SMC were corroded, makes the clock signal unstable, and battery was drop down very fast when the macbook shows apple logo, we replaced the corroded components, problem was resolved.

Go to REWA Academy to Learn More Repair Knowledge>>