: The enable signal from the EC to turn on the main power supplies.
How to diagnose No +VCC_CORE - LA- E791P Rev 2.0 - No display - SOC Problem - YouTube. This content isn't available. lalbabu.p.s.sahani
, such as a dead board or no display, so I can provide more targeted test points? la-e791p rev 2.0 schematic
connections to the charger IC and battery, as communication errors here often prevent charging even if the DC jack is fine. Schematic Access
How to diagnose No +VCC_CORE - LA- E791P Rev 2.0 - No display 7 Aug 2022 — : The enable signal from the EC to
: "Always-on" rails that must be present even when the laptop is off but plugged in.
Before diving into complex logic, verify these basic rails in order. If any of these are missing, the laptop will not reach the S0 (fully on) state: : Essential for the Embedded Controller (EC) to start. +3VALW / +5VALW lalbabu
: You can find the full Rev 2.0 diagrams on professional repositories like or via repair communities on Are you currently troubleshooting a specific fault
LA-E791P Rev 2.0 motherboard (commonly used in HP 15-bs series laptops), a highly useful piece of information for troubleshooting power issues is the SMBUS Address Table Primary Power Rail sequence Critical SMBUS & Power Address Table
: Usually the last rail to appear; if this is missing but others are present, you likely have an SOC (System on Chip) or CPU power management issue. Troubleshooting Tips No Display? A common failure point on this revision is the or a lack of Not Charging? Focus on the
If you are troubleshooting a "No Power" or "No Display" condition, checking these specific SMBUS addresses can help identify which component (Battery, RAM, or PCH) is failing to communicate: SMBUS Port 7-bit Address 8-bit Write 8-bit Read Battery (BAT) DIMM1 (RAM) Charger (CHGR) Thermal Sensor Common Power Rails to Probe