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Question about JSCAN Settings for TPMS

boontis

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I just reprogrammed my ECU for my new 35" tires and wanted to also adjust the tire pressure for the TPMS.

When I pulled up the light load setting from the ECU it was set to 0 for both front and rear, with the max load set to 36 front and rear.

My tires were sitting at 34-37 from the tire shop - no warning lights came on for the last 4 days since I brought it home.

I would have assumed that "light load" was the lower pressure to trigger the TPMS warning, and max was for an upper limit but that doesn't appear to be the case?

I've now changed the max load to 25 and aired down to 28 in the rear and 30 in the front (I have Falken AT3's in the E load rating to starting here before I do a chalk test). No warnings during a drive around the block.

Does it seem normal for the light load to be 0 from the factory? Anyone else experienced this as well? Should I up the light load to say 20 to see what happens?

Thanks in advance!
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JimLee

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It's probably scaled. The lowest setting for TPMS the computer will accept from what I've seen and read is 22PSI. A way to check would be set it to zero and then deflate your tires to below 22 psi, you should have a light if what i'm thinking is correct.
 

GtX

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I noticed the same thing and am not sure how to interpret the setting in Jscan.
 

Shak14

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Back from the dead. Having issues with the low pressure sensor popping up while at 30psi. What settings should I be adjusting within JScan? Light load or max load? Very confused.
 

Shak14

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Fixed the issue. Had to set the “max load” to 25psi.
 

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Dyolfknip74

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You know I’ve read some difficult stuff before but they make that as complicated as possible. My old superchips was just a single line item: TPMS threshold
Lol, English is not the creators first language. It's more how it's read by the vehicle though. TPMS section makes it pretty clear though.
 
 



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