HP Laptop 17-cn0003dx no power

[bobric51]

No power. Have checked power output from adapter and it is fine.  Checked DC IN power jack which is fine.  Voltage is present where DC IN power cable attaches to mother board.

[VikramTheGreat]

Hi @bobric51,

Welcome to the HP Support Community.
 

Thank you for posting your query. I will be glad to help you.

You’ve already done a thorough job checking the adapter, DC-IN jack, and motherboard voltage on your HP 17.3" Laptop PC 17-c0000 (320M3AV). Since the laptop still shows no signs of power, here are the next steps to isolate and potentially resolve the issue:

Advanced Troubleshooting Steps

1. Perform a Hardware Reset

Even if there's voltage at the motherboard, residual charge or firmware lockups can prevent startup.

• Disconnect the AC adapter and battery (if removable).
• Press and hold the power button for 30 seconds.
• Reconnect only the AC adapter and try powering on.
   

2. Check for POST Indicators

Look for signs like:

• Caps Lock blinking (error codes)
• Fan spin-up
• LEDs flashing briefly

If none of these occur, it may indicate a power rail failure, BIOS corruption, or a shorted component.

3. BIOS Recovery Attempt

If the laptop supports BIOS recovery via key combo:

• Press and hold Windows + B, then press and hold Power for 2–3 seconds.
• Release Power, but keep holding Windows + B for 10 seconds.

If successful, the BIOS recovery screen should appear.

4. Inspect for Short Circuits

Since voltage reaches the motherboard, a shorted MOSFET, capacitor, or power IC could be blocking startup.

• Use a multimeter to check for continuity to ground on key power rails.
• If you're comfortable, inspect the DC-IN circuit, charging IC, and CPU VRM area for heat or damage.

I hope this helps.

Take care and have an amazing day!
 

Did we resolve the issue? If yes, please consider marking this post as "Accepted Solution" and click "Yes" to give us a helpful vote - your feedback keeps us going!

Regards,

VikramTheGreat

[bobric51]

Thanks for helping with this problem.  I performed the hardware reset as you suggested.  I then looked for POST indicators.  I also performed the BIOS recovery attempt as you said.   No luck with any of these.  Although I am very good with a multimeter, I must say that I cannot locate the Key Power Rails that you mention.  I do not see (or smell) any evidence of a burned component.  One thing I should mention is that the Product ID is not what you have but rather it is 7E497UA#ABA.  Can you help with locating the power rails as well as the MOSFET, capacitor and power IC that you reference?

[VikramTheGreat]

Hi @bobric51,

Thank you for the detailed update and for the steps you’ve already carried out. I can see you’ve done quite a thorough round of troubleshooting already, and we truly appreciate your technical knowledge and persistence.
 

To address your request, the power rails, MOSFETs, capacitors, and power ICs you mentioned are all components on the system board. Identifying, probing, or attempting repair at that level requires specialized schematics and advanced board-level diagnostics that HP does not publish externally. Any damage that occurs during such work would not be covered under the HP warranty or service policy.
 

We completely understand how frustrating it is when a system shows no power even after resets and BIOS recovery attempts. At this stage, since none of the standard recovery procedures have worked, the most reliable next step is to have the notebook assessed by an HP-authorized service provider or HP repair center, where trained technicians can safely check the board-level power circuits.

Please help us with your HP unit serial number or the product number in a private message for further assistance.
 

Here is the link to find the product Serial number: - Click here

To access your private messages, simply click the private message icon on the upper right corner of your HP Support Community profile, next to your profile and send a private message to me with the serial number because we value your privacy.

VikramTheGreat

HP Support