I had the same problem..the issue is most likely your transformer. What might be happening, is the you are getting 12V, but essentially very little current. Most likely the impedance (resistance) on the line is very high, so check the wiring back to the transformer - you may have a burnt (as in the case with my wiring) connection causing the high resistance.
-Mr. Resistor
January 2011
I have same problem on two units. Can measure 12 V ac on both, but three different 12 V (including new) bulbs with resistance do not work, even after trying to clean contacts.
Helpless
August 2010
I have exectly the same problem. I also have 12va/c at the lamp holder and have tried several replacement bulbs.
is there no one with an answer?
Ramesh
April 2010
Check the wattage of the replacement bulb doesn't exceed the rating of the transformer - there may be a safety cutout.
Try wiggling the bulb around a bit - the contacts in the socket may be dirty and making a poor connection.
Adam
January 2010
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