HP Pavilion has power only momentarily.

[Relztrah]

A coworker's HP Pavilion dv6700 will power up for about one second, all lights flash, and then all lights go out and nothing else happens. There is nothing on-screen and no sounds of disk activity, and no beeps. This occurs with the unit plugged into the wall or running on the battery.

Where do I start troubleshooting this one?

[mjc]

Start with a known good power adapter...

[Relztrah]

I checked the power adapter with my multitester and it registers the correct voltage: 18.5V. Where do I go from here?

[mjc]

With HP laptops, there are three very common problems that cause this...the first it a bad power adapter. They use very fine/small gauge wire inside the cable and they often break right past the strain relief on the computer side connector. Check it again with someone putting a little strain on it or wiggling the cable around and see if it is putting out power even under those conditions. Generic adapters for that model are running around $10 w/ship incl on ebay with genuine HP ones running around $20. These adapters do cover a wide range of HPCompaq models...I like to keep a couple that cover different models around...but never seem to manage that.

I've had one adapter test fine on a multimeter, but putting it on the laptop it would not charge or power it. Replaced it with a new adapter and all was fine.

The next most common is the connector itself being bad. More recent (last 3 yrs or so models) use a modular connector that doesn't require motherboard soldering to replace (also for most models they run in the teens to low 20s in cost, often including shipping...but not from HP...that is ALWAYS the most expensive route). The power connector boards are running around $12 to $30 right now, same shipping deal...and just the connector itself (which you would have to solder onto the modular board is around $5).

The third most common is the motherboard itself...which until both of those other items are proven 'good', is hard to even start to figure out.

There is a 4th one...bad battery, but it isn't all that common.

[Relztrah]

Thanks MJC. I will convey this information to my coworker and let him decide how to proceed.