[SOLVED] Laptop Won't Power On - Replaced DC Jack 3x

[Appletax]

Solution: got a different laptop.


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Customer brought in a Dell Inspiron 14 (7460) for power issues. Sometimes it worked, sometimes it didn't.

Discovered the DC jack was missing a plastic piece in the center so the wires were loose.

1. Got a new DC jack. Too short.
2. Got a used DC jack and it worked fine. Customer experienced intermittent issues and brought it back. Wouldn't work right for me thereafter.
3. Got a new DC jack again that's the right length, but it won't power on. 1x it turned on for like 2 seconds and shut off.
4. Should I try a 4th DC jack? https://www.parts-people.com/index.php?action=item&id=28273

I reseated the connections (e.g. ribbon cables) multiple times. Tried a universal laptop power adapter.

Maybe the mobo was fried?

Was only able to find one:

Dell Inspiron 14 7460 i7-7500U 2.7Ghz Motherboard HD 620 29PJX 029PJX LA-D822P | eBay

Find many great new & used options and get the best deals for Dell Inspiron 14 7460 i7-7500U 2.7Ghz Motherboard HD 620 29PJX 029PJX LA-D822P at the best online prices at eBay! Free shipping for many products!

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Service tag: 647K042

 

[River Valley Computer]

Did you check to power button and cable? It could be the problem if it is intermittent turning on.

 

[Appletax]

Did you check to power button and cable? It could be the problem if it is intermittent turning on.

Yes. I pulled out the little PCB that has the power button on it and pressed it - bypassing the button above it.

Reseated the PCB cable. Doesn't look damaged.

 

[HFultzjr]

Is the battery charging?
How does it act on battery and no AC adapter?

 

[Larry Sabo]

1x it turned on for like 2 seconds and shut off

Sounds like a motherboard problem. Does this have a LED at the charger plug or at the jack edge that stays lit when you plug in the charger or after it powers off? What happens when you try without a battery installed?

 

[Dave 1973]

Sometimes a bad battery will cause this. Try a different battery or running it off AC with no battery in it.

 

[Philippe]

I would try without the DC jack... (Direct connections to the power adapter through temporary wires.)

 

[Appletax]

Sounds like a motherboard problem. Does this have a LED at the charger plug or at the jack edge that stays lit when you plug in the charger or after it powers off? What happens when you try without a battery installed?

LED stays off. Battery in or out doesn't make a difference.

Sometimes a bad battery will cause this. Try a different battery or running it off AC with no battery in it.

Done. Doesn't help.

I would try without the DC jack... (Direct connections to the power adapter through temporary wires.)

How to do?

While the power cord was plugged in, I reseated the power connector and it sparked

 

[Larry Sabo]

LED stays off. Battery in or out doesn't make a difference.

Then you have a shorted component on the motherboard.

 

[gadgetfixup]

 

[gadgetfixup]

 

[Appletax]

View attachment 12612

I’m not that smart

 

[frase]

Check continuity on the DC port, make sure no power is connected of course, refer to the schematic that @inbargains kindly supplied - Also test to see if it is getting a reading of 19.5V in a Voltage Range Check with a multimeter.

Could be a bad trace on the board itself or a damaged mosfet. Check the board for any burn out on the chips. You may need a Magnifier with a light for this, I do though I am old lol.

 

[Philippe]

How to do?

This kind of probe:


Or maybe temporary solder joints on the back of the mobo. This will bypass the connector. If the problem is on the mobo.... well, good luck!
I hate smc (surface mounted components).

 

[Diggs]

This is a Dell. It has to be a Dell charger. I don't see in this thread that you tried another Dell charger. A universal charger won't do it.

 

[SlickMinnow]

View attachment 12611

The schematics are pretty cool! Could you point me in a direction to find one for a Compaq Portable 1?

 

[gadgetfixup]

The schematics are pretty cool! Could you point me in a direction to find one for a Compaq Portable 1?

Get the board model number and I'll ask my channels for a schematic but here's a service manual that might help

http://minuszerodegrees.net/manuals/Compaq%20Portable_Plus_286%20-%20Maintenance%20and%20Service%20Guide.pdf

 

[gadgetfixup]

This kind of probe:
View attachment 12615

Or maybe temporary solder joints on the back of the mobo. This will bypass the connector. If the problem is on the mobo.... well, good luck!
I hate smc (surface mounted components).

Haha, that's not how we do it these days. If you're trying to identify or test loose SMDs you can pick one of these up for less than $20. Put the leads in slots, clamp it shut and push test. It will identify and give you a good idea if the component is good

 

[Appletax]

I ordered a used, OEM DC jack from Parts People and a used, OEM power adapter from eBay.

Stay tuned

 

[Philippe]

Haha, that's not how we do it these days. If you're trying to identify or test loose SMDs you can pick one of these up for less than $20. Put the leads in slots, clamp it shut and push test. It will identify and give you a good idea if the component is good

Yeap, I know component testers. I was trying to figure out a practical way to bypass the power connector... These probes look useful...