MoTeC Global Forum

I am trying to make an alarm for tire pressure change over time. For example if a tire loses say 8 psi in the span of 10s then I want the alarm to go off. We probably have a tire going flat.

The alarms in dash creator don't seem to allow for this? I can only do constants or a channel, greater than/less than?

In Dash Manager I can do "changed by" X psi, but still not by a factor of time.


Any help is appreciated, this is a C127 dash using dash creator.

Hi AEC47, apologies I can’t help with your query, but I’m interested if you ever came up with a solution for this? Either by tracking change over time or, another approach I was considering, the delta from the average of all other tires. For example, if the average of FL, FR, RR is 30psi and the RL tire is greater than 33 or less than 27 then trigger an alarm.

Keen to hear how you got on. Cheers, Ben

What TPMS are you running?
I have a haltech style one (looks identical) purchased from Aliexpress, it has flags in the data stream for pressure drops.

another option
filters in DC - check the 'Channel Value Change Filter' section in the help docs.
This allows you to set a filter of say 5s and it'll show the value of the channel now vs 5s ago which you could use as an alarm trigger. downside here I think is say a slow leak <1psi sec will be missed by the alarm if the diff was set to -5psi.

you could use the math function to do what you've suggested with the average of all 4 tyres -5 then in your alarm compare each tyre to the average value.

a more complicated way (potentially better) could be using math to get the average of the 3 other tyres, then use this to compare to each tyre individually.

The last two options allow the use of channel comparison and then a time element.