First thing to do is remove the battery and try it again.
This, but with some elaboration on my part ...
An unused PB 140/160/170/180 with a battery installed seems to appear dead when it has not been used for some time. I believe the issue is related to the battery, and something with the PMU which goes awry as the battery (good or bad) discharges down to nothing.
Getting it going usually involves plugging it in, pulling out the battery (not completely, just have it hanging out), powering up the PB (also press the reset switch at back), it'll probably sputter to life ... then die. Keep doing this until it comes alive again - you might need to wait ~ 10 mins and try it again. When you get to desktop, try plugging in the battery. It'll probably shut down immediately. Then try powering it up again, battery installed, it'll probably die, leave all to charge for a couple of hours ... and most likely by this time the PB will start up normally, with the battery plugged in.
If all this fails, next try reseating the CPU daughtercard. Clean the contacts with contact cleaner spray.
JB