How to troubleshoot the 7700: Test the Charging Stand


The charging stand pins should stick out approx. 1/8″ from the bottom of the base of the plastic pocket they are in.  Use a multi meter set for DC voltage and check the those pins.  They should read around 1.6 to 1.8V.  If they don’t read that then the base is bad. It could be the transformer or the wiring connections.  The transformer can be checked with an ohm meter – if either set of shows an open circuit the transformer is bad.

There are only four connections to test in the base so it should be easy to tell what part of the charging stand is bad. Test the Iron. If the base is good, place the iron in the stand and press the red button. If the light does light up while in the stand we know the connections are good and the charge stand is providing power to everything.  At this point it’s most likely the battery – though it could be an issue with the wiring to the tip.  So, you can open it up and check that to confirm that it is the battery. If the light doesn’t come on then it could be the lamp, the button assembly, the wiring inside the iron, or the connection between the iron and the base. The lamp can be removed and tested with a ohm meter and should read a couple ohms.  (You can also test it on a battery – 1.5V is enough. sometimes I use a 9v but only quickly as that’s too much for the light).  We can replace the battery and test the wiring inside as needed.

Please note opening the unit is only for trained professionals and it does void the warranty.

If you open it up, a simple ohm meter walk through of all the connections tell that they are okay.  If there are issues here with the internal wiring, we recommend returning the unit for repair here and we can ‘refurbish’ those parts.  If the connections are all good and in working condition, the only thing left is to replace the battery.

Charger Main Failure Mode List:

  • No Power to Base Transformer
  • Bad Connection in Wiring to Charging Pins
  • Not High Enough to Contact Iron

Cordless Solder Iron Main Failure Mode List:

  • Fuse Wire Open
  • Bad Connection in Wiring
  • Dead Battery
  • Dead Light
  • Red Button Not Activating the “Switch”
  • Bad Tip