Gas Fill-up data available for decoding...

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linuxkidd
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Gas Fill-up data available for decoding...

Post by linuxkidd » 2005 Aug 20 23:29

Looks like CANid 159 is for fuel tank level... Had the Mrs mark ever gallon of in comming gas. If you go to the CAN Log analyser, select 'gas intake' as the run, and CANid 159, and ZZZ [mark].

You'll notice that it's roughly every 6 or so increments of the far right hand value per gallon... I'm not certain of the top end point cause the darn pump kicked off at $49.00 ( 18.4 gallons ) of gas...

But, just another thing we can look at and use for input..
If you can read this, the light is still red.

este00
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Joined: 2005 Dec 05 20:07

Post by este00 » 2005 Dec 18 19:29

Note that some vehicles have whats called 'Fuel Level Over Bus' which is a dumb name because all vehicles have that literally. But what they mean is there are two ways this can work

One is that the fuel pump is a dumb unit. Where is has a pot inside that sends voltage to an ADC in the PCM who then determines what size tank and what level that voltage means then sends this info to the cluster to be displayed.

The other is a smart-tank. You can prolly guess that is pretty similar to the first but it has its own controller that reads the voltage in its own ADC. Then sends out the CAN message for everyone to hear. The PCM might want to know the fuel level (though maybe not), the FCM/gateway passed the info on to the Cluster, maybe the evic too.

I'm not sure which production vehicles some with either system. Most are first system style, there might not be any current production models with the 2nd, although there will be.

Anyway, what I'm getting at is there MAY be two IDs for fuel level. Or, the two systems could both output on 0x159. Just somthing to watch for if you find someone saying the fuel level signal is missing.

este00
Yes, we CAN hack!
Posts: 76
Joined: 2005 Dec 05 20:07

Post by este00 » 2005 Dec 18 19:33

PS> the reason for the 2nd system is that dcx can then save on the two fuel level signal wires going all the way to tank (ironically replaced by two can wires :? ). But, also get a lot of info from the tank, such as fuel temperature, water-in-tank , etc etc (both of those are really imporant for diesel).

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