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Old 04-10-2022 | 08:50 AM
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Default Diagnose no brake pressure

Hi Guys,

Is there a logical way to diagnose a lack of data? There is no movement in the reading while looking at live measures. The car is an 87, 911. MXL2.
Is there a way to test the sensor itself?

Thanks. Don
Old 04-10-2022 | 09:37 AM
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Switching the sensor to another channel is a good way to eliminate channel issues. Try a different patch cable or a different sensor on that channel. If the channel is set for brake pressure, what value is the dash reading right now?
Old 04-11-2022 | 09:07 AM
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Default BP Reading

Originally Posted by Matt Romanowski
Switching the sensor to another channel is a good way to eliminate channel issues. Try a different patch cable or a different sensor on that channel. If the channel is set for brake pressure, what value is the dash reading right now?
Thanks Matt. I'll check the dash reading on Tuesday night. I think it's reading some negative PSI.
Old 04-11-2022 | 09:19 AM
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Originally Posted by 993944S2
Thanks Matt. I'll check the dash reading on Tuesday night. I think it's reading some negative PSI.
If it’s reading a small negative number, single digits to low teens, that’s a normal at-rest reading, depending on the sensor calibration versus what the logger expects. You can fix it, or not.

if it’s a BIG negative number, say -467 or something in that range, it’s an open circuit. Generally will not change disconnecting the sensor or the patch cable.
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Old 04-12-2022 | 11:15 PM
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Update. The reading is -248/249 psi. It fluctuates between these. We found the connector under the dashboard disconnected. Funny enough, after an hour, we can't find the male plug it goes into. The harness off the back of the AIM dash is packed very tight in our installation. It looks like we may pull everything apart, check all the connections, make sure everything is labeled correctly. Basically, start from scratch.

Thanks. Don
Old 04-12-2022 | 11:32 PM
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If you look at your dash config in RS3, you should be able to tell which analog channel the brake pressure goes into. Then you can look for that label and plug. It's not uncommon for things to get tied up real tight and to have connections a little stressed. The easiest way is usually to cut the zip ties, pull things out, fix connections, and then tie it back up.
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Old 04-13-2022 | 09:56 AM
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Also, a good contact cleaner like Stabilant 22 can work wonders.



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