P720 work light always on with batteries, blinks on and off with power cord

[Hierogrammate]

Since yesterday, my old and trusty P720 started turning on automatically when I insert a battery. 
 

The on/off button no longer works. The only way to "turn it off" is to physically remove the battery. Annoying, but I can live with that. At least the LED still works. 

However, when I connect it to an extension cord, it starts flashing on and off every second... so using AC is no longer an option. 😕

Someone kindly suggested me (since the item is out of warranty) to hack in a secondary on/off switch.  In YouTube I've found at least some one who installed a remote-controlled dimmer switch.

All that is very cool, and worth exploring (since I'm out of warranty), but I don't know if just replacing the switch  would actually help with my problem, or if it's something deeper. 

Of course,  the only way for me to know is trying it myself, but I wondered if anyone has experienced this also, and whether they managed to fix it.

Regards,

 

Ed

[Dashley]

I've got the exact same problem with my P720. 

On-off switch has no effect regardless of power source

Light strobes (blinks) when powered with AC

Light on when powered with battery 

 

Any solutions?

[Stephanie]

@Dashley
Were you able to solve the connection problem between the power supply and the light? I''m wondering too.