Meta Description: Struggling to revive your Nokia 105 RM-908? Discover the exact USB pinout diagram, common cable faults, direct soldering points (jumpers), and step-by-step repairs for charging and data transfer.
The Nokia 105 RM-908 uses a standard Micro-USB 2.0 Type B female port. However, Nokia occasionally implemented non-standard resistor dividers on the ID and D+/D- lines to detect the charger type (standard vs. fast charging).
Before diving into the pinout, let's briefly review the device:
Unlike many Nokia feature phones of the 2000s that used Pop-Port or 2mm DC jacks, the RM-908 uses a standard 5-pin micro-USB socket. However, Nokia deliberately disabled mass storage mode. This means plugging a standard USB cable into a PC will only provide power – no device enumeration.
The key to unlocking repair and diagnostic functions lies in understanding the pinout wiring of that micro-USB port.
The Nokia 105 RM-908 USB pinout is simple but non-standard. Its reliance on pin 4 (ID) for charging detection and the absence of functional data lines on D+/D- make it unique among micro-USB devices. By understanding that pin 4 must be grounded, and that pins 2/3 are only for factory flashing, you can repair, modify, and even recover data from this rugged feature phone.
Whether you’re building a custom charging cable, repairing a broken port, or attempting a DIY data recovery, this pinout guide gives you the complete electrical map. Always double-check your connections with a multimeter before applying power, and remember: the Nokia 105 RM-908 may be simple, but it rewards careful, precision work with years of additional service.
Further resources:
Have a tip or correction about the NK105 RM-908 pinout? Share your experience in the comments below. Nokia 105 Rm 908 Usb Pinout
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The Nokia 105 (RM-908), released in 2013, remains a staple for reliability and simplicity. However, unlike modern feature phones that use standard Micro-USB or USB-C ports, the original RM-908 relies on a 3.5mm AV-style charging port and a proprietary internal interface for data and flashing.
Understanding the pinout is essential for technicians performing firmware updates, unlocking security codes, or repairing charging paths. Internal Data and Flashing Pinout
Because the Nokia 105 RM-908 lacks an external USB data port, flashing and unlocking must be done via the F-Bus interface located on the motherboard. Technicians typically use a JAF, ATF, or Infinity BEST dongle connected to these specific test points: VPP: Programming voltage. TX: Transmit data. RX: Receive data. GND: Ground.
BSI: Battery Size Indicator (used to put the phone into "Test" or "Local" mode). Connection Point VBUS (+5V) Power input for charging Near the 3.5mm jack contact GND System Ground Any metal shield or battery negative BSI Local/Test Mode trigger Middle pin of battery connector RX/TX Data Transfer Internal motherboard test pads Charging Path and Jumper Solutions
If your RM-908 is not charging, common hardware solutions involve bypassing faulty components with jumpers. Nokia 105 (2023) User Guide - HMD
Report: Nokia 105 RM-908 USB Pinout and Connection Guide
Date: October 26, 2023 Subject: Technical Pinout Configuration for Nokia 105 (RM-908) Device Model: Nokia 105 (Nokia Feature OS) The Ultimate Guide to Nokia 105 (RM-908) USB
A: Check the 10kΩ resistor between pin 4 (ID) and ground. It may be damaged. Also verify the charging IC (usually a small 6-pin IC near the USB port) is getting VBUS.
The Nokia 105 (RM-908) uses a standard 5-pin Micro-USB connector. Below is the hardware-level mapping.
| Pin | Signal Name | Function | Connected to (on PCB) | Typical Voltage | |-----|-------------|----------|----------------------|------------------| | 1 | VBUS | +5V Charging Input | Charging IC / PMIC | 5.0V (max 6.0V) | | 2 | D- | USB Data Minus | RAP3 CPU (via series resistors) | 0–3.3V logic | | 3 | D+ | USB Data Plus | RAP3 CPU (via series resistors) | 0–3.3V logic | | 4 | ID | USB ID | Pulled to GND via 0Ω resistor (for OTG detect – not used) | GND | | 5 | GND | Ground | Main ground plane | 0V |
Shell: Shield Ground (connected to GND via ferrite bead).
Below is the standard pinout for the micro-USB connector used on the Nokia 105 (RM-908). This applies to the phone’s charging/data port wiring where the micro‑USB connector is exposed on the PCB.
Pin assignments (micro‑USB, looking into the plug with contacts up):
Notes and practical details:
If you want, I can:
The Nokia 105 (Model RM-908) is a classic 2G feature phone originally released in 2013. Unlike modern iterations that use USB-C, this specific model features a Micro-USB port located at the top of the device for charging. USB Pinout Overview
The Micro-USB port on the RM-908 follows the standard 5-pin configuration used for mobile charging and basic data functions. When the phone is viewed with the port facing you (and the wider side of the trapezoid at the bottom), the pins are ordered 1 to 5 from left to right: Pin Number Description Pin 1 VCC / VBUS +5V Power Supply for charging. Pin 2 Data - (D-) Negative data line (often used for software flashing). Pin 3 Data + (D+) Positive data line. Pin 4 ID Typically not connected (NC) on this model. Pin 5 GND Ground / Negative terminal. Common Repair Scenarios
Charging Issues: If the device shows it is charging but the battery level does not increase, it may require a "charging jumper" to bypass damaged motherboard traces.
Flashing & Unlocking: For technical repairs like software flashing or bypassing a forgotten security code (default is 12345), the D+ and D- lines must be functional to allow communication with repair software.
Replacement: If the physical port is damaged, it can be replaced by soldering a new standard Micro-USB Type-B jack onto the PCB. Technical Tips
ESD Safety: When opening the device for pinout repairs, ensure you use proper ESD protection to avoid damaging sensitive electronic components.
Battery Contacts: The RM-908 uses a removable battery (typically 800mAh) that connects via three metallic pins on the motherboard. Ensure these are clean if the device fails to power on after a USB repair.
For visual diagrams and step-by-step soldering guides, reputable mobile repair communities like Mobile Master Prince Mobile Lab or iFixit often provide specific "charging way" schematics for this model. Nokia 150 (2023) user guide: Keys and parts - HMD Model: Nokia 105 (RM-908) Release: 2013 (first generation