It had been a while since we had worked on one of these older models 2014 MacBook Pro 15-inch, as most of the repairs we handle involve newer MacBook. However, with our extensive experience in MacBook repairs, this was a challenge we were ready to take the laptop started up and displayed a battery level of 32%, but within minutes, the battery drained completely and refused to charge. Additionally, the charger did not light up when plugged in.
Table of Contents
Initial Inspection
The first step was to verify the issue by connecting our own known-good charger. As expected, the charger did not light up, confirming that there was indeed a power issue. We then moved on to inspecting the board. Your MacBook should now be in sleep mode. After around ten minutes it will boot back up, with AC power or battery power.
Identifying the Board Model
The motherboard in this MacBook was identified as board number 820-3777-A. Fortunately, we had schematics and board-view diagrams for this model, making the troubleshooting process more systematic and efficient.
Step 1: Inspecting the Charging Circuit
Since the charger did not light up, we needed to investigate the charging circuit. One of the common failure points in these MacBook models is the ISL6259 , which is responsible for managing power input and battery charging. You should check for a faulty adapter and broken charging cable first. To do so, you need to make sure your MacBook is switched on and plugged in.
Thermal Camera Analysis
Using a thermal camera, we scanned the motherboard to check for any heat signatures indicating active or shorted components. A suspicious heat spot was observed around the ISL chip, which pointed to a possible failure of this component.
Step 2: Testing Current Sense Resistors
Before replacing the ISL chip, we decided to test the current sense resistors, as these are known to fail in MacBook and can cause similar charging issues.
- Relevant Resistors:
- R7121 and R7122 (should be 10 ohms each)
- R7151 and R7152 (should be 0.2 ohms each)
Upon measurement:
- R7151 and R7152 read correctly at 0.2 ohms.
- R7121 and R7122 gave abnormal readings of 450 kiloohms and 8.7 megaohms, respectively.
This confirmed that both current sense resistors had failed, which is quite unusual since typically only one goes bad at a time.
Step 3: Replacing the Current Sense Resistors
Despite suspecting an ISL chip failure, we decided to start by replacing the faulty current sense resistors. We removed them, cleaned the pads, and installed new 10-ohm resistors from our inventory.
After soldering the new resistors in place, we rechecked the resistance values:
- Both resistors now correctly read 10 ohms.
With the resistors replaced, we plugged in the charger again, hoping for a green light. However, there was still no response, which indicated that the ISL chip was indeed faulty.
Step 4: Replacing the ISL Chip
We carefully removed the defective ISL chip and prepared the board for the new one. A new ISL chip was sourced and soldered in place with precision.
After soldering, we cleaned up the area to ensure no solder bridges or debris could cause issues. Once satisfied with the installation, it was time for the moment of truth.
Step 5: Testing the Repair
We plugged in the charger and watched closely.
Success! The charger light turned green, indicating power detection, followed by an orange light, signaling that the MacBook was now charging properly. The repair was a success.
Conclusion
This MacBook Pro 15-inch (2014) had suffered from a dual failure: faulty current sense resistors and a defective ISL chip. By methodically diagnosing the issue and replacing the necessary components, we were able to restore full functionality.
This repair highlights the importance of systematic troubleshooting, patience, and the right tools. Whether you’re a professional or a hobbyist, having access to proper schematics, quality replacement parts, and reliable equipment is key to successful MacBook repairs.
How to 2014 MacBook Pro A1398 Won’t charge Fixed
MacBook Pro 15-inch, as most of the repairs we handle involve newer MacBook. However, with our extensive experience in MacBook repairs, this was a challenge we were ready to take the laptop started up and displayed a battery level of 32%, but within minutes, the battery drained completely and refused to charge.
If you use your MacBook Air Or Pro to run your business, you don’t have the time to send it away for a repair. Lucky for you, Reformtech can have your device looking and running like new in just a few hours. We have locations across Kolkata, so your local location is just a short drive away. Don’t let your productivity suffer because of a broken device, and we can get your MacBook Air & Pro back up and running in no time and for the lowest price around.
We hope our customers are confident that they are getting the best deal on their repair. We have a low price guarantee that promises that if you can find a lower advertised price for the same repair, we will match and beat that price. Our standard warranty is valid at Reformtech, protecting your device no matter where you need us. Description: Looking to repair your MacBook Air & Pro? We Can Fix It, From MacBook Air & Pro Screen Replacement, Battery Replacements, Keyboard & Case, Adware Removal and More.
ReformTech is a highly reliable Laptop and Smartphone repair service provider that offers on-site repairs for various brands. We specialise in fixing hardware issues, including screen replacements, keyboard replacements, RAM upgrades, SSD upgrades, and even motherboard repairs. Contact us at 8100257620 for fast and efficient service.
