Thursday, 30 June 2011

Piaggio X9 Evolution 250 scooter incorrect mileage odometer reading

A Piaggio X9 scooter that had electrical problems after being in the rain.

Water had got into the clocks and the electrics were not happy, many dash lights randomly lit.

After drying out, the scooter was all ok except that the distance / mileage was reading 99998 km or 62498 m (bike had been set to miles but had reverted to km).







This was not good ! service history and re sale is hurt with the mileage so wrong, also it wouldnt increment ! so basically broken.

A google showed its not uncommon, water gets in at the edges of the push buttons, I found a forum post that recommended sealing the buttons and putting bags of moisture absorbing gel inside the clocks.

Surprise surprise the clocks were opened to find that the buttons had been sealed and little bags of gel put inside already by whoever had the same problem last !

The sealent had gone off / was not the correct type and had let water back in.

I also found people on the web talking about the mileage going wrong, reading 99998. I figured the mileage had got corrupted.

The mileage is stored in a serail eprom 24c02



I removed the chip and read its contents, the chip read fine and comparing the contents to a good dump I found on a greek forum, it looked valid.

This was the first thing that made me think that the chip and contents were fine, just that maybe the MCU could not read it at boot up.

Here is how I powere the clocks on the bench.



I checked that the serial eprom was powering up by checking continuity to the supply rails, they were ok.

I checked continuity of the data pin to the MCU,this was present.

I checked continuity of the serial data clock pin to the MCU and could find no connection, this did not seem right !

The data pin also connected to a large pad on the edge of the pcb, presumably for factory programming, sure enough the clock pin did not go to any of these pads, however one of the MCU pins did.

I fitted a link from the eprom clock pin to this pad and.....



Result, the correct original mileage now reading from the eprom at power on.



It looks like the link for this track in the multi layer PCB had gone.

The clocks were re sealed and re fitted to the bike, all reported to work ok, mileage reading, incrementing and storing ok.

16 comments:

  1. Hello,

    Great post and so much details. Do you have an electric scheme for this circuit board. My scooter does not show the speed that I am going and it does not keep track of km.
    Thank you in advance.

    Srdosolja.

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  2. Thanks for the comment. Im afraid I dont have a schematic for the board itself, but the manual here does show the pin out of the connectors which may help a bit. Page 75 and 76 for connections.

    http://www.scribd.com/doc/17726048/Piaggio-X9-Evo-250-EN

    I would say that if your mileage shows correctly but doesnt go up becasue of no speedo signal then your problem shouldnt be too serious, hopefully just related to the speedo pickup. Good luck.

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  3. Thanks for the link but I already have that manual. Maybe I did not present the problem correctly. The mileage is still it is not changing and the speed does not show. The pins are OK. When I opened the board I saw that one resistor and one diode are burned out. I replaced them but now the mileage is changing but needles on the analog board are not moving. Before only the speed was not moving but now also the temp, gas and tachometer are not moving :(
    That is why i am searching for schematics.

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  4. One more thing though. Can you please check on your board what markings are on this transistor because I can not read them on my and i think it is broken.

    http://users.beotel.net/~vladanp/transistor.jpg

    Thanks.
    Srdosolja.

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  5. Hi, Im afraid I dont have access to the board anymore so can not check its id or if it is NPN / PNP / FET.

    You may be able to work out by looking at the other small signal transistors on the board and comparing it to how and where they are routed, then just try any common small signal transistor in its place.

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  6. Hello! This problem for me because the scuter, I can not work there at 99,998 gasoline and the wather no time indicator goes up to max both of them, we wrote to each other at the epromot someone got content, B9 00 71 48, I enjoy it 45000 km corresponds to nothing but! can not be explained somehow maskeppen because unfortunately I do not know English, and Google Translate does not pay anything korekutl's not really understand it! Thank you!

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  7. Hi can you tell me what element is this with orange cable with number 1 mark,because on my two are burnt,and black on right side.Thanks

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  8. I just had mine fixed by http://www.midlandmileagecorrection.co.uk/ yesterday

    Years ago while watching my bike, the mileage went from 2000 miles to over 45000 miles. I searched and searched on the internet and local bike shops to see if they could help. No one could do it, I even sent the speedometer away many times but in the end midland mileage correction came to the rescue... the bike was up and running within the hour.

    Thanks

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  9. Hi, would you know which chip controls the flashing of the indicators ?

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  10. Wow, you are amazing. You explained this tutorial really nicely. Thanks for sharing.
    --------
    mopeds

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  12. I have the exact problem and i've checked for contuinity. The 24c02 gets Vcc and ground ok, data from 24c02 to the MCU is ok, however the clock is not ok. The only continuity i found is from the chip to the large debug pad on the edge of the pcb and nowhere else. I can't see the other side of the pcb because of the lcd and i don't want to unsolder it. So the only choice i have is to make an external link just like you, but i don't know where. Can someone check the pcb and tell me where else the clock pin is connected in order to make an external connection?

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  13. Hello
    That was my problem too. I did it and it works.Thank you very much!
    Daniel from Hungary.

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  15. Thank you very much Lowfinger for this solution. It helps me to solve the same problem!
    Regards from Serbia!

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    Replies
    1. Your welcome, really glad to hear it helped out.

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