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Convertible won't power on

Tupin

Experienced Member
Joined
Jun 7, 2009
Messages
436
Location
St. Louis, MO
I just got one of these in today and to my dismay it doesn't seem to power on, no signs of life at all...power supply is lit up but nothing else. Any ideas?
 
Work through the basics. Check all the voltages coming out of the PSU. Check for any signs of battery leakage / corrosion damage. If all that checks out (and you have the facilities) try a supersoft diagnostic ROM.
 
I presume by "convertible", that you are writing of the IBM Convertible, the IBM 5140.
I do not own an IBM 5140, but here are some of my thoughts:

There are three power options for the 5140:
1. AC Adapter (100-240 Vac), 40W
2. Battery Charger, 3W (charges the battery only - does not power 5140 itself)
3. Automobile Adapter, 38W

Is it option 1 that you have?

Assuming so, does the machine power up without the battery? By the way; I do not know if that is a valid thing to do on a 5140. To me, it just sounds like a useful thing to try.

However, the following earlier post by billdeg suggests that a dead battery should not stop the 5140 from at least displaying something:
"The reason the clock with the question marks appears when you boot is that your battery is dead or needs to be charged up and the time/date are not saved in the battery save state memory. Just hit F1 to bypass. If you're not also seeing the "battery dead" icon on the same screen, you're in luck, you can probably recharge your unit enough to hold the date and time if you reboot. Either way, it does not matter. As long as your power supply works, the system will be fully functional you just won't be able to save the date. "
 
Getting 15v out of the power supply. Doesn't power on with or without the battery in. Next thing in line, the ROM?
 
Getting 15v out of the power supply. Doesn't power on with or without the battery in. Next thing in line, the ROM?

I would try something easier first. Carefully remove the keyboard and then reseat and /or remove some of the RAM, then retry to power. Could be a loose or shorted RAM. There may be other things under the keyboard to investate before you jump to the motherboard. Also be sure the rear-attached components are correctly fastened.
 
Don't know if I'm looking at the right thing, but I'm just seeing a bunch of surface-mounted chips...
 
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Are you sure you have the right AC Adapter? There was a guy selling an IBM 5140 on ebay a couple of weeks ago with what looked to be the wrong power source. Also, does your 5140 have the backlit screen or one of the two non-backlit screens?
 
I don't know if the convertible has any similar issue but with an NEC Multispeed laptop I thought was dead until another member here posted about having it plugged in for 12 or 24 hours to recharge the CMOS battery. Of course, I really don't recall if the 5140 even had that capability so it may be a non-issue but was an easy fix that I didn't expect to revive this "newer" system. (Something to remember for later portables.. even had to do that with my Xybernaut MA-IV before it would turn on after some time in storage).
 
I have a 5140 with the backlit screen and the IBM P/N for the Power Adapter is: 2684292

The Computer Reset site says that different power adapters are used for the backlit screen and for the other two non-backlit screen versions. I don't know if this is true or not but it's possible.
 
That is the exact power adapter I have.

I can't seem to remove the RAM cards, they appear to be secured somehow?
 
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