W510 complains about power supply wattage

[tpribors]

Well, i just posted that I was looking for a replacement for my T540p that was a convenience upgrade. Well, my W510 that I use for photo and DVD work has started misbehaving.

This machine has worked for years, what maybe close to 10 now? It's been a brick.

Suddenly last week when I booted the BIOS screen complained that the power supply didn't meet minimum wattage. This machine uses the straight barrell 20V 135W power supply. Like I said, it's worked for a long time. I twisted things and it came back. Now today it's permanent.

runs very slowly and the display is barely visible. The system sometimes works for short periods of time. It blinks in at full power display and then goes out a few seconds later.

I know that the W510 won't run with a 90w supply - I tried that years ago when I was sharing the desk spot with a T60. And the power supply on my W520 uses a keyed connector since it's the 170w supply. However, the 135w supply did in the past work on the 520.


I don't know if it's the power supply or if the power detection logic on the mother board has gone bad.

Is there a way in either Windows or the BIOS to determine the wattage of the power supply that is connected? I don't know if it's the detection logic on the mother board or the supply that's bad. If not in the normal thinkpad utilities is there some other "thinkpad savvy" utility that can show the info?

Cheers
Tony

[RealBlackStuff]

I would check the middle pin of the barrel-plug and the DC-in itself.
Might have gone wonky.

[tpribors]

I did check it, the thing does supply DC so it's probably the sensing/configuration resistor. It was just sitting there - nothing moved for months...

I ordered a clone from Amazon. Free return so if it doesn't work I'm not out anything.

[BillP]

I did check it, the thing does supply DC so it's probably the sensing/configuration resistor.

Did you measure the resistance from the sense pin to ground? I don't have a 135W power supply but my 170W supply measures 1900 Ohms from the sense pin to ground.

[axur-delmeria]

I did check it, the thing does supply DC so it's probably the sensing/configuration resistor.

Did you measure the resistance from the sense pin to ground? I don't have a 135W power supply but my 170W supply measures 1900 Ohms from the sense pin to ground.

According to Thinkwiki http://thinkwiki.org/wiki/Power_Connector#Signal_Pin, the resistance between the center signal pin and ground is zero ohms for the 135 watt charger.

[tpribors]

Just to follow up. I bought a new charger and that fixed it. Back on the air!

Now the HDD on the W520 bought the farm too. I don't use either that much but because they have Firewire/1394 interface for my scanner I need to keep them alive.

Saw an X1 at Costco. Very nice machine.