Speedo not reading right

[scarlett155]

Hello all. Just picked up a 2008 GTI SE 155. She's a great machine, 115 hrs, runs awesome... My only issue is the Speedo doesn't read correctly. It appears to read about half of the actual speed measured by my phone with a GPS app. All I saw on the display was 27-28 and my gps measured it at 55.2 or something like that. Where can I start to diagnose it? could it be a bad connection somewhere? Do I need to take the speed sensor off the back? I'm new to most of this but am just dangerous enough in my garage to be able to tackle most things!! Thanks for any ideas you have!!

 

[ski-d00]

Does the paddle wheel at the rear spin freely?

 

[scarlett155]

Does the paddle wheel at the rear spin freely?

Yes it does

 

[4tec hoarder]

replace the paddle wheel with a CanDoo GPS speed sensor

 

[scarlett155]

replace the paddle wheel with a CanDoo GPS speed sensor

Where can I find that?

 

[dcm0123]

Where can I find that?

$170 on line search.
Part Number -> 9509 [9509] - $169.00 : CANDooPro LLC, Diagnostic Tools

Check to see if you damaged a paddle on the sensing wheel. You can buy an aftermarket wheel as I did.

 

[scarlett155]

$170 on line search.
Part Number -> 9509 [9509] - $169.00 : CANDooPro LLC, Diagnostic Tools

Check to see if you damaged a paddle on the sensing wheel. You can buy an aftermarket wheel as I did.

Just the wheel itself?

 

[dcm0123]

This Ebay one states it fits later models. Also an OEM one on Amazon 2x the price but not sure of the fit.
You may also want to make sure if someone did replace it, the flat side of the four lobes should be facing the water coming towards the machine (as shown below) otherwise it may not spin fast enough.

If your wheel is intact and spins freely, I doubt this is your problem.

NEW SeaDoo Paddle Wheel for Speed Sensor Speedometer 4tec gtx gti rxp rxt xp gsx | eBay

 

[Ironmikea]

My 2 cents. I am going through this now with my Utopia 205. I purchased the candoo gps speedometer sensor (9508) which is advertised as a direct replacement and couldn't get it to work. There are a couple of issues with replacing the Sea Doo paddle wheel. The Utopia and I suspect the older wave runners are the same, have an electric speedometer which is looking for a 4 - 5v pulse. To complicate this further, supposedly Sea Doo made active and passive paddle wheels, the first needs an external voltage source to work and the later does not. The candoo Sea Doo part doesn't produce the correct voltage for an standard electric speedo so there is a hack required to do to get it to work like the paddle wheel. Might I suggest you test the paddle wheel first. Disconnect the paddle wheel, hooking the leads up to a voltmeter and rotate the wheel slowly and seeing if it outputs voltage. Most likely it is working since you are getting a reading. I wasn't able to get an output voltage from the paddle wheel installed but I did connected 5V directly to the signal lead and ground of the speedo and did see the gauge needle move to 40 mph to 0. This happens because it's looking for a pulse.