MacBook Pro A1706 Question Mark Folder and SSD Not Detected: Liquid Damage Repair

The A1706 Question Mark Folder Problem

The MacBook Pro A1706 (13-inch, 2017, Two Thunderbolt 3 ports - also known as the non-Touch Bar model) is prone to a specific failure pattern after liquid damage: a question mark folder on startup, and complete SSD non - detection. The SSD is physically present and undamaged, but the Mac can't communicate with it.

When you power the machine back on after addressing the initial liquid damage (replacing corroded components like the CV3215 charge pump or applying cleanup), you'll get the blinking question mark folder - the Mac's way of saying it can't find a bootable drive.

This doesn't mean the SSD is dead or needs replacement. It means the logic board can't communicate with the SSD because of a broken trace or failed component on the NAND power delivery circuit.

Why This Happens After Liquid Damage

Water ingress happens in consistent locations: through the keyboard or the vent intake on the top of the machine. It flows across the logic board and always settles in one particular corner - where a critical probe point lives that controls V2.7 NAND power delivery.

This isn't random. Liquid damage on the A1706 fails in the same spot every single time because of board design and water flow physics. The probe point is small, susceptible to corrosion, and when it fails, the NAND chip stops receiving stable power.

Understanding NAND Power Delivery: The V2.7 Voltage Rail

The Apple NAND storage chip requires a precise 2.7-volt power supply. On the A1706, this voltage is created by a buck converter that steps down the main power rail and is routed through a specific trace path:

The probe point in step 3 is where the problem occurs. Probe points are tiny test contacts used during manufacturing and repair. They have a small gold - plated top surface that resists corrosion, but the trace underneath has exposed copper.

How Probe Point Corrosion Breaks NAND Detection

When liquid damage occurs, contaminants activate and the copper beneath the solder resist corrodes extremely quickly - much faster than gold or solder. The probe point looks intact from the top, but underneath the resist coating, the copper trace has completely disintegrated.

Once the copper trace is gone, the V2.7 NAND enable signal stops reaching the buck converter. The NAND chip never receives power. The Mac's boot process looks for the SSD, finds nothing, and displays the question mark folder.

The tricky part: the probe point can look completely normal on the surface. You need to inspect the corners and edges with magnification. If you see discoloration or burnishing around the edges of the probe point (before the solder resist begins), that's a red flag. Poking into the resist with a probe will reveal if the trace has crumbled away.

How to Identify a Corroded Probe Point

Repair Techniques for Corroded Probe Points

Option 1: Jumper Wire Bypass

The most direct repair: solder a small jumper wire from a good PPBUS source (like pin 1 of the C9400 capacitor or the closest PPBUS_GSH test pad) directly to the buck converter input, bypassing the corroded trace entirely.

Option 2: Trace Repair

If the corrosion is localized to a specific section, you can:

• Scrape away the solder resist to expose the trace beneath the corroded probe point
• Remove any remaining corroded copper or vias
• Re - route the trace with 0.25mm or smaller jumper wire to reconnect the path
• Test continuity before reassembly

This approach takes more time and precision but restores the original signal path.

Option 3: Component Replacement

If damage extends to nearby resistors or capacitors:

• Replace corroded resistors (especially R9350)
• Replace any damaged capacitors in the V2.7 rail
• Rework the buck converter if components are lifted or damaged
• Reapply solder resist and conformal coating to prevent future corrosion

Why SSDs Are Fixable (Unlike Traditional Hard Drives)

Apple's NAND storage is physically soldered to the logic board and sealed in epoxy. The SSD itself is almost immune to liquid damage because most of the electronics are encapsulated. Only the connector edge is exposed, and those gold contacts resist corrosion.

The real damage occurs on the logic board itself-the power delivery circuitry, traces, and components that communicate with the NAND. This is why a "not detected" SSD doesn't mean the storage is lost. It means we need to fix the board's ability to talk to the SSD.

Once the V2.7 NAND power is restored and the data lines are working again, the SSD comes back online. The data is intact. The machine boots normally.

Prevention and Probe Point Best Practices

For Repair Technicians

For MacBook Owners

When Professional Data Recovery is Needed

If your A1706 MacBook Pro is showing a question mark folder and the SSD isn't detected, professional board - level repair is almost always necessary. Here's why DIY approaches typically fail:

Our Austin repair lab handles these cases daily. We have the microscopes, soldering stations, and expertise to diagnose and repair probe point corrosion, restore NAND power delivery, and recover your data.

The Takeaway: Always Check Your Probe Points

Probe points are small, easy to overlook, and they fail in the same predictable pattern every time. Anywhere you see liquid damage on an A1706 MacBook Pro, check the probe points in that area really well. Poke them in the corners. Make sure they haven't disintegrated underneath the solder resist.

The gold plating on a probe point does resist corrosion better than exposed copper. But once you get away from that gold - underneath the resist or at the edges - the copper corrodes extremely quickly. Much faster than solder will.

So remember: Always poke the edges of your probe points, especially when something critical (like NAND power) is running straight through it. A single corroded trace can bring the entire SSD detection system offline. And that's something to watch for.