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Voltage gauge inaccurate

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Old 07-18-2022, 03:38 PM
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PC-85-928S
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Default Voltage gauge inaccurate

1985 S3 US, auto
charged battery





voltage from battery car not running


voltage with car running



dash gauge


Old 07-18-2022, 04:41 PM
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Speedtoys
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Voltage losses from at least..9 different connections between the electrical system and the gauge itself are gunna impact this reading..

Age is an issue too, IF the path is clean to the gauge, and to ground, it will STILL be off from the battery, or front post.

ONCE you know its a clean solid path, you can adjust for losses by adjusting the gauge, if you like:

Old 07-18-2022, 06:26 PM
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Mrmerlin
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replace fuse 10 the instruments fuse , add deoxit 100
Old 07-18-2022, 08:01 PM
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Originally Posted by Mrmerlin
replace fuse 10 the instruments fuse , add deoxit 100
That's two connections cleaner....
Old 07-18-2022, 09:16 PM
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NOTE on my black 82 after I took the pod apart and readjusted the gauge and put it back together.
Dr Bob posted this lil tidbit of fuse replacement.

Damn if the gauge was reading 14.5. SB 13.5
Yep pod apart and readjusted back to where it was....
Old 07-18-2022, 11:57 PM
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After I hardwired mine it seems like all of the gauges are more responsive and accurate. They're getting a lot more juice through 20 gauge wires than they were through the printed circuit panel I guess.... also I clean the posts on the back of the gauges during the process so I'm sure that reduce some of the resistance

Last edited by mkhargrove; 07-18-2022 at 11:59 PM.



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