Couldnt really find a section for this..

[jxx]

great work festy, thanks

[festy]

X05ff is the checksum function.

[jxx]

X0961 instant fuel calc?

any ideas on the checksum for the mc code? runs but fails diag if it's not 7100

[festy]

What's mc?

[jxx]

*microcontroller

once disassembled then assembled following hex add's are changed to FF once changed back to their orig values works again, can manipulate the values for these to get the 7100 checksum correct without causing issues if code is changed.....

Code: Select all

0009 00   000A 00   0158 90   0159 03   015a E7
0696 86   0697 87   0738 00   0739 00
0906 00   0907 00   0E3B C1   0E3C 90

needs 0FFE & 0FFF added as 00 each for size checksum

not sure if that's anything important or just my luck assembling

[Streetholden]

Wow, i didnt realize this was still going. I do have a question in relation to this topic, but its not quite the same.

The odo gets its read out from the speedo? Meaning if i plunged in a dash, wired in a speedo sensor to make the speedo work the odo would tick up if i was to spin the speedo sensor with a drill or such?

Just thinking outside the box :/

[festy]

you created a monster when you posted your original question 6 months ago

To answer your question: yes, spinning a VSS should wind it up - but I think this was discussed a few pages back, but using an oscillator to send pulses in place of a VSS.
Someone (me maybe?) posted a rough estimate on how long it would take - it's definately quicker to order an ebay programmer from China and wait for the postman than to make a significant change to the odo by faking VSS pulses.
You'd also have to be careful not to pulse too fast or you might bend your speed needle

Are you still looking to get your odo reprogrammed?

[Streetholden]

Ah true, cheers mate, nah im not looking to program mine, i just like thinking up little mad scientist projects to do out of sheer boredom. Im not that crash hot with computers and programs which is why i thought of this way. And to stop the needle bending.. Remove it?

[Streetholden]

So after a talk with Festy i realized a drill or similar, if i made it run at 200km/h would take 4000hours. He mentioned sending pulses through an "oscillator" would work better, ill be checking this out and see what i discover.

[jxx]

wouldn't need the hole cluster to do it that way, just feed the signal into the lcd unit while powered up (4/5 wires 1-2 gnd's, pwr, ign, pulse) that'd save causing damage to the speedo unit, still a very sloowww method the mention of an oscillator again reminds me of the old 555 pulse generator truckies used to use to defeat the early gen speed limiters, so it wouldn't have to be a complicated circuit.
555 timer, few caps and a 1:1 audio transformer/isolator from memory, could make a useful tool to test the calibration of speedo's.