PeachParts Mercedes-Benz Forum - potentiometers New ANY NEED?

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potentiometers New ANY NEED?

WE have an outlet for new Potentiometer's I am curios as to how many would be interested in the perchase of this Item? :D

Are you referring to the dash light dimmer unit ?

I know the older 126 cars are potentiometers that directly connect to the power. The 2nd gen 126 cars are actually PWM controllers.

Quote:

Originally Posted by TnBob (Post 2944790)

Are you referring to the dash light dimmer unit ?

I think, "just-n-time" reffering to the KE- mass air flow sensor's potentiometer. :rolleyes:

I am interested. Price?

I just jumper it on the cars where it fails. 100% power is barely bright enough as it is. :D

Quote:

Originally Posted by Dr. Sternschnuppe (Post 2944826)

I think, "just-n-time" reffering to the KE- mass air flow sensor's potentiometer. :rolleyes:

Yes I am refering to air flow unit.:cool:

potentiometer price

Quote:

Originally Posted by brewtoo (Post 2944835)

I am interested. Price?

the price would be around $50.00:D

Quote:

Originally Posted by pawoSD (Post 2944858)

I just jumper it on the cars where it fails. 100% power is barely bright enough as it is. :D

WTF, are you talking about !

Is potentiometer made by Bosch? P/n 3 437 224 035?

If new potentiometer made in China - it is, unfortunately, a bad deal. :(

Quote:

Originally Posted by maska (Post 2945639)

WTF, are you talking about !

He's referring to the rheostat dimmer for the instrument cluster and dash lights. Usually the left most knob on the cluster.

Early unit are simple rheostat potentiometer. Later versions (at least in 126) are PWM control units. They're backwards compatible too!

Quote:

Originally Posted by JamesDean (Post 2946097)

Thats more clear, Thanks

Quote:

Originally Posted by JamesDean (Post 2946097)

Interesting, if they're PWM they should be able to dimmer a set of LEDs

Quote:

Originally Posted by tbomachines (Post 2946335)

Interesting, if they're PWM they should be able to dimmer a set of LEDs

Not necessarily, they are likely too slow and you'd end up with a strobe instead of steady lighting. An LED responds to pulses a lot differently (faster) than an incandescent....

Quote:

Originally Posted by tbomachines (Post 2946335)

Interesting, if they're PWM they should be able to dimmer a set of LEDs

Quote:

Originally Posted by pawoSD (Post 2946396)

Not necessarily, they are likely too slow and you'd end up with a strobe instead of steady lighting. An LED responds to pulses a lot differently (faster) than an incandescent....

I'm waiting for my soldering iron to heat up so I figured I'd give it ago:

From what the scope says, it looks like the PWM controller outputs about 160 Hz signal. Here's the datasheet on the IC: http://www.datasheetcatalog.org/datasheet/stmicroelectronics/1408.pdf

http://i.imgur.com/YN1Ywl.jpg

I had some random 2V, 20mA Red LED sitting around, I threw a 500 Ohm resistor on it and here's the result. It does indeed dim... With better/brighter LED's you could probably achieve a better result.

For wiring reference:
http://i.imgur.com/7HNkLl.jpg

Video, I didnt see any strobing effect when I filmed this:
http://img.photobucket.com/albums/v6..._aMVI_8150.jpg