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Speedo and tach problem Rx1 -03

Discussion in 'Electrical' started by mushkin, Dec 22, 2008.


  1. mushkin

    mushkin Extreme

    Messages:
    101
    Location:
    Ornskoldsvik, Sweden
    Hi


    I got some problems with my Rx1 Mtn -03. My Speedo and tach doesn't work :(

    When i start the engine, head + tail lights seems to work fine. The tach does its self test (needle goes to max rpm and then down to 0), every symbol etc in the LCD/speedo lights up as usual.

    After this, the tach stays at 0 rpm, the speedo is totally empty (Doesn't even show something at all), and the odometer has " - - - - - " which is flashing.
    The speedo also says MPH, but it should be KM/H because it's sold in Sweden.

    I've read something about relays, fuses etc, but when the display, with thumbwarmer indications etc works, I don't think its a relay?

    Ideas?

    Regards /Bjorn
    Sweden.
     
  2.  
  3. kinger

    kinger VIP Member VIP Member

    Messages:
    6,083
    Location:
    Clear Lake, IA
    Did you check the wiring down at the base of the hood where it can rub on the hinge and short out over time? Check that your ground is tight on the battery also.
     
  4. mushkin

    mushkin Extreme

    Messages:
    101
    Location:
    Ornskoldsvik, Sweden
    No I haven't. I'll check it asap and come back with a status report :)

    Thanks
     
  5. Len Todd

    Len Todd TY 4 Stroke God

    Messages:
    2,282
    Location:
    Baldwin, Michigan
    You may want to check to connector on the back of the Gage. They frequently come loose. You may want to check the other connector at the ECU too.
     
  6. apltx08

    apltx08 TY 4 Stroke God

    Messages:
    1,957
    Location:
    Ottawa,Ontario
    It could also be the famous SPEEDO bearing acting up!
     
  7. Len Todd

    Len Todd TY 4 Stroke God

    Messages:
    2,282
    Location:
    Baldwin, Michigan
    The Drive Shaft Bearing typically does not affect the Tach. The Speedometer and Tach are driven by different outputs from the ECU. Both the Tach and the Speedometer are acting up. So, ... the problem is most-likely common to both circuits. The connectors at the ECU and Gage are common to both circuits, are easy to check and frequently are reported to be the cause of what is being seen. So are the wires at the ECU common to both and known to have been a frequent problem.

    However, it could be a input to the ECU, as you are indicating. But, first we should rule out the connector's and check for wire chaffing around the ECU. Then, if we still have a problem, it is be good time look into some of the individual ECU inputs.

    As a rule of thumb, I typically work way my back from the indication of the problem, until I find the root cause. That way, nothing gets missed. Just kinda the way I prefer to go about it. So, ... there is my nickel for the night.

    Merry Christmas Guys!
     
  8. mushkin

    mushkin Extreme

    Messages:
    101
    Location:
    Ornskoldsvik, Sweden
    Hey and thanks alot for the help so far.

    Ground connection to the battery is OK, all fuses (right side of the air filter box) are OK.


    Thanks again for the help, lets see what I find tomorrow.

    Merry Christmas!
     
  9. mushkin

    mushkin Extreme

    Messages:
    101
    Location:
    Ornskoldsvik, Sweden
    Okay, I have now disconnected the cable harness from the instrument housing and the ECU. It looks okay from what I can tell. The cable harness itself seems to be OK.

    What is the next step?
     
  10. Len Todd

    Len Todd TY 4 Stroke God

    Messages:
    2,282
    Location:
    Baldwin, Michigan
    So, .. To recap:

    Two Symptoms = no speedo and no tach. But the other parts of the gage work.

    The harness is not chaffing on the frame in the area around the ECU casuing a short(s). You have verified this.

    The ECU connector is clean and making solid connections. You have verified this.

    You have removed and reinstalled the Gage Connector and it is making solid connections. You have verfied this.

    Still no change. Eh?

    We are down to the ECU. I say the ECU becasue you are getting two separate parts of the gage that are not being driven properly. Yet other parts of the gage are. So you have power to the gage. But the two inputs to the gage (From the ECU) are not driving it.

    Are you sure that the ECU connector is good?

    If it is not the ECU, then it has to be the gage.

    I'll have to think a while on the best way to test this. Got to go to xmas party.
     
  11. mushkin

    mushkin Extreme

    Messages:
    101
    Location:
    Ornskoldsvik, Sweden

    Three symptoms = No tach, no speedo, no ODO. The ODO numbers are replaced with flashing "- - - - -" Rest of it works.

    As I can see, harness is not chaffing on the frame, not throug a cable anyway.

    The ECU connector looks nice and clean. No signs of damage or what so ever.

    The instrument connector also seems clean and undamaged. I think it's pretty hard to tell if there is a 100% contact, because I find it hard to verify this with a "ohm meter". Connector - instrument.

    Perhaps i need to check every cable individually between the ECU connector and the instrument connector? The only problem then is, I dont really know which cables from the ECU connector leads up to the instrument?


    Thanks again!

    /Bjorn
     
  12. Len Todd

    Len Todd TY 4 Stroke God

    Messages:
    2,282
    Location:
    Baldwin, Michigan
    I think the problem is NOT wire chaffing between the ECU and Gage. There are too many signals that went out all at once. However, see the last paragraph below. Chaffing or a broken wire could have casued the ECU to fail.

    There is a Yellow-Black wire that comes from the ECU to the Gage. That is the Tach wire. Remove the drive belt or lift the track off the ground so you can safely rev the engine a bit in place. With the gage connector in place, pierce the Y-B wire in a location that is not near any metal surfaces and measure for voltage DC as you Rev the sled up and down to 5000-6000 RPMs. Do not over rev, especially if you have the drive belt off. If you do not see any DC voltage change, try measuring for AC. If you are not seeing any AC voltage change either, then the Tach signal is not coming from the ECU. If you are seeing voltage coming from the ECU, then it either has to be the Gage Connection or the Gage itself. If you are not seeing any signals from the ECU, then my bet is on the ECU, Especially if you checked all the wiring going in and out of the ECU.

    One other thing about the wiring to the ECU. You mention some chaffing but not to the point of rubbing through. On those wires that appear chaffed, is it possible that they have broken? You can disconnect these wires at the sensor/primary element end and at the ECU and measure them for continuity (i.e. Zero ohms). If I saw any chaffing, I would do this before I bought a new ECU.

    From what you have told us, my gut is telling me it's the ECU. :-(
     
  13. mushkin

    mushkin Extreme

    Messages:
    101
    Location:
    Ornskoldsvik, Sweden
    Hi, and thanks for the help Len.

    About the chaffing, I cant se the wires, but some chaffing have occured on the harness cover , (black tape?)
    So there is no signs of any cable what I can see.
     
  14. Len Todd

    Len Todd TY 4 Stroke God

    Messages:
    2,282
    Location:
    Baldwin, Michigan
    Test all affected wires for continuity (i.e. Zero ohms end-to-end).

    Separate the individual wires and tape them individually. Then put some sort of protective hose (rubber or vinyl hose slit lengthwise, etc. They do have material for this at auto parts shops, too.) over the group of wires in that area. Tape the protective cover in place
    .
     
  15. Len Todd

    Len Todd TY 4 Stroke God

    Messages:
    2,282
    Location:
    Baldwin, Michigan
    Hey mushkin!

    Where are you at on this?
     
  16. mushkin

    mushkin Extreme

    Messages:
    101
    Location:
    Ornskoldsvik, Sweden
    Hey

    I had to replace some exhaust gaskets and it took like a week for my yamaha dealer to get them. I will start the engine tonight and give it a try.
     

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