Zoom Nikkor 24-120mm f/3.5~5.6D IF - camera not reading/setting aperture

<p>I just tried to use my wife's 24-120/3.5-5.6 lens (that's the first (non-VR) version) on my D300 and realized that I can't set the aperture from the camera. The lens was at the smallest aperture setting (f/22) and locked at that position - yet the D300 kept reading f22 no matter how I tried to change the aperture from the camera. Only when I turned the aperture ring on the lens, did the reading on the D300 change. When I put the lens back on the F100 where it normally resides, it showed f - - but occasionally - when changing focal length - it showed an aperture value; this value was replaced by f - - as soon as I turned the meter turned off and back on again. Examining the lens contacts more closely, I realized that one contact pin was retracted and is without spring tension - this seems to be the likely culprit for the "failure to communicate". Question: is that something I can fix myself - possibly through buying a new piece with the contacts (or do I have to replace the entire CPU) - or is this something I have to send the lens to Nikon for service/repair? Has anyone taken that particular lens apart - how difficult is it to replace those contacts, or the entire CPU? If it has to be the CPU - do I have to program the new one?<br>

Thanks in advance for your help.<br>

Dieter</p><div></div>

<p>f-- means the camera thinks that the lens has no CPU, or the camera cannot communicate with the lens' CPU if there is actually one. That slightly damaged contact point is likely the problem. Years ago a friend of mine has that problem with his 500mm/f4 P lens. Repair cost was like $100 or so back in the late 1990's.</p>

<p>Does the contact pin flop around, when the lens is inverted ... indicating a spring that's not where it should be? Needs surgery then.</p>

<p>Or is the pin stuck down due to a bit of dirt or a burr interfering with the spring's ability to return the pin to its outward travel?<br>

The latter can be determined with a bit of judicious pin wiggling with a straight pin or dental pick. I won't advise a lubricant, but if there is dirt it, may be dislodged with manipulation.</p>

<p>Jim</p>

<blockquote>

<p>Does the contact pin flop around, when the lens is inverted ... indicating a spring that's not where it should be?</p>

</blockquote>

<p>Yes, it does flop around. I have pulled the piece up a little but can't see that there is any way to get at the contact pin from the backside - so not sure what surgery could be performed save replacing the whole contacts unit.</p>

<p>Repair estimate from Nikon was some $163 - about the same ballpark the lens sells these days for. Guess I will either be attempting a repair myself or listing it for parts at the big auction site.</p>