How To Program ROM Chip for iPads with CD3217 and IPhone 14 Pro Max – No Modem Firmware After RF Layer Swap: Difference between pages

IPhone 14 Pro Max – No Modem Firmware After RF Layer Swap
Device	iPhone 14 Pro Max
Affects part(s)	Motherboard
Needs equipment	Microscope, Hot Air Station, Multimeter, Schematic + Boardview for iPhone 14 Pro Max, Tweezers, Flux, Soldering tools
Difficulty	◉◉◉◌ Hard
Type	Soldering

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Revision as of 23:13, 30 July 2025

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Problem description

An iPhone 14 Pro initially came in with “No Service” (no IMEI on dialer), but modem firmware was still present. The device was previously worked on by another technician who attempted to resolve the issue by swapping the RF (bottom) layer. After the swap, the phone began showing “No Modem Firmware”, making the situation worse.

This issue is due to mismatched board configuration resistors — specifically the Board ID, Platform ID, and SKU ID resistors — between the original and donor layers.

Symptoms

No IMEI on dialer
Modem firmware missing (blank under Settings > General > About)
Cannot connect to any network

Diagnostic Steps

Check for Modem Firmware:
- Navigate to Settings > General > About
- If “Modem Firmware” is blank, baseband is not initializing.
Confirm RF Layer Swap:
- Check with client or inspect board for signs of reball or swap on the RF side.
Inspect Board Config Resistors:
- Check if Board ID, SKU ID, and Platform ID resistors are missing or incorrectly placed on the donor RF layer.
- Use microscope + boardview/schematic to locate and match resistor values from the original board.

Repair Steps

Identify Original Config Resistors:
- If original RF board is available, measure and note resistor values at Board ID, SKU ID, and Platform ID.
Transfer Resistors to Donor RF Layer:
- Carefully remove the config resistors from the original board.
- Solder them to the corresponding pads on the donor RF layer.
- Ensure alignment and no shorts between pads.
Inspect and Clean:
- Check for cold joints or missing components.
- Clean area with IPA and test continuity.
Assemble and Test:
- Power on the phone.
- Go to Settings > About and check if “Modem Firmware” appears.
- Dial *#06# to confirm IMEI is now visible.
- Test network signal and cellular connectivity.

@@ Line 1: / Line 1: @@
+{{stub}}
 {{Repair Guide
-|Affects parts=Logic Board
+|Device=iPhone 14 Pro Max
-|Needs equipment=Soldering Iron, Hot Air Station, Microscope
+|Affects parts=Motherboard
+|Needs equipment=Microscope, Hot Air Station, Multimeter, Schematic + Boardview for iPhone 14 Pro Max, Tweezers, Flux, Soldering tools
 |Type=Soldering
-|Difficulty=4. Specialist
+|Difficulty=3. Hard
 }}
-{{stub}}
 == Problem description ==
 <!--
 Provide a concise description of the issue here. Be  as specific as possible to help readers quickly determine whether or not this is the exact problem they are facing.
   -->
+An iPhone 14 Pro initially came in with “No Service” (no IMEI on dialer), but modem firmware was still present. The device was previously worked on by another technician who attempted to resolve the issue by swapping the RF (bottom) layer. After the swap, the phone began showing “No Modem Firmware”, making the situation worse.
+This issue is due to mismatched board configuration resistors — specifically the Board ID, Platform ID, and SKU ID resistors — between the original and donor layers.
-Some iPads using the CD3217 USB-C controller IC can develop a no charge, no boot, or low voltage negotiation issue. This typically happens after liquid damage or a power surge. Replacing the CD3217 alone doesn’t fix the issue, because the connected ROM IC is often corrupted or damaged.<blockquote>⚠️ Important: The CD3217 and ROM chip are not paired, but the ROM stores crucial firmware/data required for CD3217 functionality. If the CD3217 fails, it often damages the ROM, and a new CD3217 will not function unless the ROM is replaced or programmed.<br /></blockquote>
-[[File:IPad-Not-Charging.png|thumb|Symptom 1 (Fig. 1) -- iPad Not charging and stuck at 5.00V and 0.744A]]
+[[File:Placeholder image.jpg|thumb|Example image (Figure 1) -- No image yet. Help expand this page by uploading it!]]
 == Symptoms ==
 <!--
 Detail all measurable or observable symptoms in this section.
 -->
-* Symptom 1 (Figure 1)
+* No IMEI on dialer
-** USB-C power meter shows only 5V — no voltage negotiation (should be 15)
+* Modem firmware missing (blank under Settings > General > About)
-* Symptom 2
+* Cannot connect to any network
-** New CD3217 IC installed but still no charge
-== Solution ==
-<!--
-If the issue has a single, specific solution, provide it in this section and delete the sub-headers below. Otherwise, if there are multiple potential causes for the problem, outline the process of identifying the root cause and offer corresponding solutions below.
--->
-* Replace both CD3217 and ROM IC (See Fig 2)
-* Program a new ROM using JC V1S Pro
-* Install both chips
-* Charging will be restored
 === Diagnostic Steps ===
-# [[File:CD32&ROMIC.png|thumb|Fig. 2 -- The CD3217 IC and the Ace ROM IC]]Visual Inspection
+# Check for Modem Firmware:
-#* Look for signs of corrosion/Look for shorts around the CD3217 and ROM area
+#* Navigate to Settings > General > About
-#* Check for burnt ROM chips or CD3217
+#* If “Modem Firmware” is blank, baseband is not initializing.
-# Voltage Testing
+# Confirm RF Layer Swap:
-#* Use USB-C power meter or bench power supply
+#* Check with client or inspect board for signs of reball or swap on the RF side.
-#* Plug in USB-C and check if iPad negotiates proper voltage
+# Inspect Board Config Resistors:
-#* 5V = error (bad CD3217/ROM or negotiation issue)<br />
+#* Check if Board ID, SKU ID, and Platform ID resistors are missing or incorrectly placed on the donor RF layer.
+#* Use microscope + boardview/schematic to locate and match resistor values from the original board.<br />
 === Repair Steps ===
-=== Step 1: Remove Damaged CD3217 & ROM ===
-* Desolder both the faulty CD3217 and the adjacent ROM IC
-* Clean area properly, ensure all pads are intact and usable
-=== Step 2: Prepare New CD3217 + New ROM IC ===
-* Use a fresh CD3217 IC from a trusted supplier
-* Get a blank ACE SPI Flash chip — compatible size for your board
-=== Step 3: Program the ROM Chip ===
-[[File:Align-rom-jc.png|thumb|Fig. 3 -- Match the dot on the ROM chip to the triangle on the JCV1S Pro ROM Read/Write Module.]]
-Option A: JC V1S Pro Server
-* Use JC V1S Pro with their ROM Read/Write Module
-* Install and align the ROM chip to the triangle on the programmer. (See Fig. 3)
-** Step 1] Press check on the programmer and it will detect the SPI chip.
-** Step 2] Select 'Open' then 'ServerFile' (Note: Your V1S Pro needs to be connected to WiFi for this to work)
-** Step 3] Choose corresponding file required for the model of your iPad.
-** Step 4] Click Write and Confirm write
-Option B: Donor Board ROM Dump
-* Pull a working ROM chip from a donor board of the same model
-* Use JC V1S Pro to read and save the dump locally
-* Click write and select the file and flash the dump onto your blank ROM IC
-* Store dumps in a labeled folder (example: iPad Pro 11 2nd Gen CD3217 ROM.bin)
-[[File:IPad Succesfully Charging.png|thumb|Fig.4 -- iPad Successfully charging after CD3217 and Ace ROM replacement]]
-=== Step 4: Reball & Install CD3217 ===
-* Reball and solder new CD3217 in place
-* Ensure all surrounding passives are intact
-=== Step 5: Install Programmed ROM ===
-* Solder the newly programmed ROM chip in original location
+# Identify Original Config Resistors:
-* Clean with IPA and inspect joints under microscope
+#* If original RF board is available, measure and note resistor values at Board ID, SKU ID, and Platform ID.
-* Verify Charging by plugging in a charger that supports 15V charging (See Fig. 4)
+# Transfer Resistors to Donor RF Layer:
+#* Carefully remove the config resistors from the original board.
+#* Solder them to the corresponding pads on the donor RF layer.
+#* Ensure alignment and no shorts between pads.
+# Inspect and Clean:
+#* Check for cold joints or missing components.
+#* Clean area with IPA and test continuity.
+# Assemble and Test:
+#* Power on the phone.
+#* Go to Settings > About and check if “Modem Firmware” appears.
+#* Dial *#06# to confirm IMEI is now visible.
+#* Test network signal and cellular connectivity.