Thread: Tachometer died
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Freybird Freybird is offline
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Join Date: Feb 2003
Location: Frederick, Md
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Tachometer died

Tach part number 911 641 301 05
On a spirited drive Sunday morning the tach suddenly went to 0rpms. Everything else was quite normal. When I shut the car down, the tach did blip up to 1000rpms and then back to 0rpms.
I've searched all over these forums and found instruction on removal and disassembly of the sealed tach case. Upon opening, the smell of fried electronics was evident. The resistor circled in the picture is burned open. (sorry for the bad cell pic) Appears to be 100ohms, but its too roasted to tell definitively. Does anyone know the actual value of this resistor or where to find a schematic? This tach has the 7pin connector on the back.
I'll be monitoring the charging voltage tomorrow as I suspect this is what caused the failure.
Thanks in advance for any information.
'86 911 Coupe Corner bal track aligned
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Old 05-09-2011, 06:52 PM
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