My tach stops working when it is too hot and sometimes when it get really cold.
Does any one have or know were I can get wiring diagram? And know if I can wire in an after market?

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If everyone was the same, this would be one boring world.

1937 Chevy pu
1983 300D Turbo (250K) Daily driver
1983 300D Turbo spare motor(250k)
1965 Chevy C-10

Unscrew you tach amp.Clean pins and sockets.Check to see if sockets push down when screwed. If so,press the sockets up,after using some super glue gel.Then support socket from slipping back down while you screw amp back on.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran, deutschland deutschland uber alles uber alles in der welt

Usually the amps fail, I replaced mine, no more problems.

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83 SD

84 CD

Sometimes thats the case.But usally the wire coming from pickup to socket,shrinks with age.Add virbration and there you have a socket not seating well.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran, deutschland deutschland uber alles uber alles in der welt

^ Yes and it's cheaper.

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83 SD

84 CD

One of the forum members :Techguy" makes an up grade for the Tach Amp.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

thanks for the info, but still new to Mercedes, where is the tach amp?

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If everyone was the same, this would be one boring world.

1937 Chevy pu
1983 300D Turbo (250K) Daily driver
1983 300D Turbo spare motor(250k)
1965 Chevy C-10

In the 300sd it is a black round plug on the Driver's side fender well that unscrews. It has a small plastic strap that holds it in place.

Mine was giving intermittent results due to the plug inside not making contact with the socket. It turns out to that the plug's insulation shrinks leaving a space at the top of the plug.

Unscrew the plug and pull the inner plug out. Use something to fill the space. Some suggest a garden hose washer. Replace cap and this may fix your problem if its a loose tach amp.

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This area is typically used to brag about one's current or former automobiles.

^ Yeah, the 123 in the pic is an '84 meaning it has a different pick up and no amp, but it's located in the same place.
The SD (white one) is an '83 meaning it has the amp system, you can tell as the cover (the amp itself) is taller.
Follow the gray wire (gonna be dirty) from the bottom of the amp bracket down around to the engine block, the other end of that wiring harness has a Hall effect sensor that picks up, magnetically, every crank rotation off a pin. I have yet to see that fail, but it's possible.

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83 SD

84 CD

cool!!! thanks!!!! I will look into.

__________________
If everyone was the same, this would be one boring world.

1937 Chevy pu
1983 300D Turbo (250K) Daily driver
1983 300D Turbo spare motor(250k)
1965 Chevy C-10