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I recently purchased an old BMW 318is (1994 model, so it really is old) and received two pairs of keys.

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The keys come with a silver and black pad that has 4 buttons on it. I'm not sure what each button does and some guidance would be appreciated. As far as I can tell the opened keypad button is to disable the car's immobiliser and that's as far as I've gotten.

The key itself has a button on it too but it's broken. What does the broken button do and is it worth repairing it?

p.s. Googling for the keys didn't yield a single photo of the same keypad.

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I have a feeling the fob(that's the thing is called aparrently) is there to compensate for the broken button on the key. The bottom two are supposed to be lock and unlock. The other two I don't know, but they're probably alarm on and alarm off. I put this as a comment because I'm not sure. – Juann Strauss May 8 '14 at 11:19

I would leave this as a comment, but I cannot.

The button on the BMW key is a light. There should be a bulb visible next to the metal key section. To open it up, press the button and slide the inner assembly out. You should see the battery, bulb and contacts.

As for the aftermarket fob, I would agree with Juann Strauss that the buttons are lock/unlock and arm/disarm the alarm - but this is purely a guess without knowing the brand or model.

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