Econometer

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Bonymaenjack
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Post Fri Jan 07, 2022 8:52 am

Good day I wonder if anyone else has experience of this . and do you know what maybe the cause : When sitting stationary with the engine running on occasion my Econometer will fluctuate reading swinging from right to left and back to stop. this happens with out the car moving nor the engine being revved , below is the description from Wikki of how the system operates .

The econometer is dependent on the tachometer and the speedometer; therefore, anything that stops these two will also affect the econometer.

However, if these two are working normally but your econometer is not (especially if it reads Minimum or Maximum, but nothing in between) then the fault usually lies in the interior circuitry; the econometer is not receiving a speed signal from the speedometer. This is most likely caused by failing/ burnt out circuitry, or leaking SI batteries, and the only practical solution is to replace the dash cluster.
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30316
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Post Fri Jan 07, 2022 12:10 pm

Sounds like a dodgy wiring or a dry joint on the instrument cluster pcb.
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Contours
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Post Fri Jan 07, 2022 6:39 pm

My economy gauge was doing the same thing until I changed the Service indicator batteries years ago. Never an issue since
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Bonymaenjack
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Post Sat Jan 08, 2022 10:28 am

Thanks both , not sure to look regarding the dry solder joint but it'll be out there somewhere . The batteries are a fairly recent replacement and everything else works as they should but something else to consider .
onthames
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Post Sat Jan 08, 2022 11:22 am

Bonymaenjack wrote:
Sat Jan 08, 2022 10:28 am
Thanks both , not sure to look regarding the dry solder joint but it'll be out there somewhere . The batteries are a fairly recent replacement and everything else works as they should but something else to consider .
There's something on the wiki about capacitors / solder joints in cluster, can't find right now but if you can't find yourself I'll have a proper look when I get home later