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How do you test the Infared sensors in the doors and the trunk?

With an Infra Red flashlight?!;)

Explain how you can tell if one of the sensors is weak or not working correctly with a flashlight!

The receivers in the doors and trunk are just that-receivers. There is a test in the diagnostic manual that tell you if they are working or not, but the "strength" is determined by the output of the key. The receiver has no "strength", it's thought of more as an antenna. These receivers can go bad though. If you are sure you have a good IR signal from the key, as determined by battery voltage in the key and/or testing the IR output with an IR tester card (available for example from Radio Shack for testing any other IR remote, usually advertised for testing TV remote controls), then you can thing in terms of replacing an IR receiver. In case of reduced range for the IR key (less than 10 feet or so) I would first suspect a weak battery in the key. Do you have another key to try? What is the problem with the remote locking system?

Gilly
pa I think he was joking about the IR flashlight.

Quote:

Originally posted by gillybenztech
The receivers in the doors and trunk are just that-receivers. There is a test in the diagnostic manual that tell you if they are working or not, but the "strength" is determined by the output of the key. The receiver has no "strength", it's thought of more as an antenna. These receivers can go bad though. If you are sure you have a good IR signal from the key, as determined by battery voltage in the key and/or testing the IR output with an IR tester card (available for example from Radio Shack for testing any other IR remote, usually advertised for testing TV remote controls), then you can thing in terms of replacing an IR receiver. In case of reduced range for the IR key (less than 10 feet or so) I would first suspect a weak battery in the key. Do you have another key to try? What is the problem with the remote locking system?

Gilly
pa I think he was joking about the IR flashlight.

The system seems to work ok except when you lock doors the red light in the door handle continues to blink for 15-20 seconds and the book says it should blink for 3-4 the key has a new battery still no change. Dealer says they can't find whats wrong.

If the range is OK, (works good up to about 10 feet from the car) then I would say the key and the IR receivers are doing their jobs and to not focus on either of these. If the only thing wrong is the red light blinks longer than programmed, and all else is functioning OK, possibly it is just some strange problem with whatever flashes the confirmation light on the receiver (I believe the IR control module does this). Or it could be a warning of some type. I can't think WHAT it would be warning though. Are all the doors locking properly, also the trunk? Maybe there is a problem with one of the door jamb switches so it thinks a door is still opened, or the switch for the trunk light.

Gilly

How are ATA codes read??