How do I clean the DX contacts/censors

Try cleaning the contacts in the camera and clean the film canister. You can also try putting self adhive tape on the DX Area of the film cassette and set the film speed ASA manually.

What is the DX code on a film roll?
The DX code is the silver and black pattern on almost every film cartridge. Inside most electronic film cameras, there is a series of metal pins that read the code and tell your camera what your film speed is.

Film DX-code sticker - Decisive Moment

You are the only person to encounter this issue, so you may need professional repair.

https://www.google.com/search?q=Minolta+Freedom+Zoom+70C+not+reading+DX+Codes

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Are you talking about the camera reading the DX coding of the film canister? If so, when you place the film in the left side the camera automatically sets the film speed based on the DX coding of the film cartridge. Look in where you place the film canister there you will see the little brass buttons.

What speed film? Does the roll have the DX markings (the black-and-silver rectangles)? If it doesn't, what happens if you set the film speed manually?

Okay. Just bear in mind that the exposure meter is going to be two stops off, unless you're getting the film pull-processed.

The Maxxum 3Xi unfortunately does not have a way of overriding the Camera Automatic Sensing portion of the DX encoding standard. That is, if the film cartridge has the DX encoding, the camera will set itself to the indicated speed.

However, if the film cartridge is NOT encoded, the camera will set itself to ISO 100. So, if you tape over the magnetic encoding on the cartridge...

The CAS is not the barcode on the film cartridge, but the rectangular patches of conductive and nonconductive material.

Take a look at http://en.wikipedia.org/wiki/DX_encoding for more information about the DX encoding.

You can't. If the film cartridge has the DX markings then the camera will automatically set it to the correct speed. Without the DX markings the camera goes to ISO 100. You can adjust this by using exposure compensation. For example, if you have ISO 200 film loaded without the DX markings, set the exposure compensation to -1.0 and you will get the proper exposure.

Since it has automatic ISO setting from 25 to 3200, you should use DX-film. However, most of the auto-setting cameras (in fact all I have come across) default to ISO 100 or 200 when using non-DX films. Consult your user manual to confirm which one.

I'm not familiar with your exact model so what follows is generic to many film SLR cameras and assumes that the camera is already empty:-

Open the back of the camera by pulling upwards the rewind crank on the top left hand end of the camera (as viewed from behind). The back of the camera should pop open a little, open it all the way.

Before fitting the film, check if the film can is DX coded. It will have DX printed on it somewhere if it is, but will also have a large area bare metal squares interspaced with printed black squares or rectangles. if the film is not DX coded then look for an ISO number, ASA number or DIN number and note it somewhere.

Drop the roll of film into the space at the left of the camera, and push the rewind crank back down to secure the film canister. Pull out the film leader across to the right hand end of the camera. Often there are printed instructions or diagrams showing what to do. Your camera probably has an easy loading system in which you pull the film leader until it's level with a printed line and then close the camera back until it clicks.

Turn the camera on, normally it will staert whirring as it autoloads the fil onto the take up spool. If successful the number one will appear in the film counter display within a few seconds. If not then open the camera back and try again.

What you do next depends on whether the film is DX coded or not. There will either be a dial or a menu item which allows you to set the film speed, for DX coded films set the control to DX or to AUTO. If the film is a rare non DX-coded one then you need to set the speed manually. Select the correct ISO number in the menu. If your film had an ASA number then use it as an ISO number and if it had a DIN number then look up DIN to ISO conversion online.

If this has solved your problem then please return the favour by rating my answer, thanks.

Is the film loaded correctly? Have you tried reloading it? Also is it flashing DX too? That would mean the film speed is not DX coded so you need to set the film speed manually.

jackson rook,

the speed of the film may be to high if your camera has dx coding contacts in the film chamber. otherwise---- film in camera or not it has no effect on meter operation. move the advance lever to the right slightly and push down on the shutter release button slightly to turn meter on.

Check the little gold DX contacts inside the film chamber. If they are bent, try to straighten them (Carefully they can be brittle) If they are stright, try cleaning them with a VERY LITTLE amount of denatured alcohol. If all this fails to help, take it into Nikon.