Tire size battery disconnect

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Herckules35

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Hey guys
2021 warlock. Stock 17” tires.

I had a guy (subcontracted to Tam dealers in the area to reprogram BCM for lift kits, etc) reprogram my BCM for my 20” tires, which replaced my OEM 17” tires.
Spedo/odo working perfectly, by the math: 1Km at 100kkm/h= 36 seconds. My time was 35.9.
When the programming took place, I had three tires in pressure alarm. I also had the pressure threshold set to 248kpa/36 psi. The cold pressures at the time were 248, as new tires were just installed so I knew that pressure to be true. The factory spec was 296kpa/43psi. The alarms did not clear after 45 minutes of highway driving.
I later inflated to 296kpa/43psi and alarms cleared. Deflated back to 261/39. Cold night, pressure was down and same 3 tires in alarm again. Some highway driving after work brought them up to 275/40 all around.

I’m thinking the TPMS alarms are hung up in the system.
Will disconnecting the battery and discharging the system erase the programming the subcontractor did? Will this force reset the TPMS and accept the 248kpa/36psi threshold? He said he was using the CanBus system.
 

Brian2081

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You are going to have to get back into the BCM and set your alarm threshold a little lower, OR add 5 psi of air to each tire while they are still warm. That way when they cool off they should drop back to about 40 psi.
 

Mister Luck

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Count your miles after 50 the TPMS should communicate with all 4 if not you might be drawing interference or have a bad sensor.
You should have a SGW bypass to change settings or the dealer will.
 
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