Originally posted by Kelvunlee I have another question. How do I properly diagnose a broken DC motor? Is there a way for me to use a multi meter to check the electrical contacts? I don't think there was a point when I thought the motor was "failing", it just stopped working all of a sudden.
Is there a way to "warm up" the DC motor like they do with the SDM motors?
You'd need data of the DC-motor.
The "warming up*" (using a hairdryer or similar) only worked with some of the original SDM lenses made by Pentax.
The newer lenses which have that name as well like the DA18-270 SDM are made by Tamron and use their PZD motor (and
Differences are explained here:
The 5 Lens Autofocus Drive Types Explained - Articles and Tips | PentaxForums.com
*warming up can be misleading because some use that word just for
a)"trying to use the lens several times until it works again, this method does sometimes work
b) opening the lens and moving the motor with a screwdriver which indeed won't do wonders at all
c) method b) but applying some thin oil which in some cases works