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Bench Test Anti Slosh Module DAC7624

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Old Aug 21, 2018 | 03:26 PM
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Default Bench Test Anti Slosh Module DAC7624

My fuel gauge is off by about 1/4 tank. When I fill the tank up, it shows as 3/4 full. When the low fuel light goes on, I only get as much as 14 gallons in the tank.

I bought a spare on eBay and it's actually not working at all....oh well...

Is there anyone that knows how to diagnose these things? I opened one up in hopes of finding a bad solder joint, but all "looks" good to the eye.

 
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Old Aug 21, 2018 | 03:38 PM
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Same with mine, Full shows 3/4.
 
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Old Aug 21, 2018 | 07:55 PM
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I had the same thing happen a few years ago. The problem was the wiper inside had worn thru causing the false reading. I put in a replacement that has worked fine since. I have also heard that the float gets saturated with fuel doesn't float as much as it should.
 
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Old Aug 22, 2018 | 07:42 AM
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If you’re talking about the wiper on something in the gas tank....I’m afraid I’m going to live with this issue....
 
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Old Aug 23, 2018 | 06:31 AM
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Vee,

As you probably know, the A-S module is designed to smooth the voltage output signal to mitigate the changes of the voltage input signal that occur because of the inevitable tank level movements incurred through acceleration, deceleration, cornering etc.

The problem happens because the capacitors in the A-S module which are used to support the voltage control "leak" over time. The resulting reduced voltage signal then causes the lower gauge reading.

Repair of the unit involves replacement of the capacitors. I have seen somewhere a specification for some suitable capacitors and ill try and dig it out if I can remember where I saw it.

cheers

Paul
 
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Old Aug 23, 2018 | 01:46 PM
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That would be super awesome. In the meantime, I read that by jumping terminals 3 & 5 (light green and light green/orange stripe wires) aka the middle horizontal and top vertical terminal, the gauge should read normal. If it doesn't, its likely the sender.
 
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Old Aug 23, 2018 | 02:12 PM
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Doesn't bother me, just takes longer for the gage to start moving downward from 3/4.
 
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Old Aug 23, 2018 | 04:13 PM
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Vee,

Removing the module and jumping those 2 terminals will effectively give you a straight pass-through of the voltage signal from the sender direct to the gauge, together with any expected fluctuations as the fuel moves around. Be aware thst you will lose your low fuel warning light which is driven only if the module is in circuit.

cheers

Paul
 
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