Tach only ready about half

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C-Rock
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Tach only ready about half

Post by C-Rock » Wed Mar 28, 2012 10:06 pm

My Tach seems to only be reading about half, also fuel gauge seems to wonder around and seems to be real slow. Could the contact's be dirty?

Cliff

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anglin
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Re: Tach only ready about half

Post by anglin » Thu Mar 29, 2012 12:03 am

C-Rock wrote:My Tach seems to only be reading about half, also fuel gauge seems to wonder around and seems to be real slow. Could the contact's be dirty?
Cliff,

It's generally not an issue with contacts. A tach that reads low or not at all is often subject to failed cold solder joints in the circuit board. Here's my repair photos and process from my road car maintenance thread:

viewtopic.php?f=37&t=10805&start=30

Also, Ed brings up good points about the potentiometer. So, that's worth a check too.

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Re: Tach only ready about half

Post by $KRILLA » Thu Mar 29, 2012 3:00 am

Great info how bout a lazy Scorpio tach,do you know if its the same set up?

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Re: Tach only ready about half

Post by Ed Lijewski » Thu Mar 29, 2012 7:14 am

Yes.

YMMV ;)
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C-Rock
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Re: Tach only ready about half

Post by C-Rock » Thu Mar 29, 2012 7:52 am

So is it just a matter of removing the gauge cluster getting the circuit board out and hitting each solder joint with some new solder?

Cliff

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Re: Tach only ready about half

Post by wicked93gs » Thu Mar 29, 2012 8:38 am

You dont even need new solder..in fact its better you dont add any..just heat it up and reflow it
'66 Mustang coupe 4.6l DOHC, T45 etc
'77 Celica Liftback GT SRT engine swap/MA5 trans swap
'87 XR4Ti b234f+he351ve+t5 in progress
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C-Rock
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Re: Tach only ready about half

Post by C-Rock » Thu Mar 29, 2012 8:44 am

Will do

Thanks

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