2010 22SSV Speedometer Problem

Just took out my new 2010 Supra 2010 SSV. We have a problem with the speedometer. It fluctuates greatly... up to +/- 20 miles per hour. This is causing the perfect pass to not work correctly. When the speedo indicates the speed is slow the engine revs up and when the speedo indicates too fast the engine backs off almost to idle. This condition continues and makes using the cruise worthless. Has anybody seen a similar issue? If so, what was the cause. Obviously I'll be taking back to the dealer for warranty repair but any information would be appreciated.

Check your paddle wheel under the boat, make sure you are not missing any paddles. Make sure it spins freely by hand. This would more than likely be the problem.

Dealer told me that the speedometer is GPS based and not a manual pickup???

Ah this is not good, for now you could try using the rpm based mode on the perfect pass to get you by......maybe it is having a hard time reading the sats or your in void zone

Hello, I have a 2010 Supra sunsport. I am having the exact same problem. I was wondering what the outcome was of this problem for you? I have contacted the dealer and they seem puzzled by the problem.

I had this same issue about 3 weeks ago. It worked fine all day and then went back out for an evening set and it was doing as the OP described. I thought maybe there was a problem with some of the satellites it was reading. I ran manually that evening without a speedo which wasn't fun and fortunately the next day everything went back to working normally. I chalked it up to a satellite problem but maybe I was just fortunate.

Solar flares? I saw on weather.com that they are getting ready to publish space related weather! The only other thing I can think of would be if something is obstructing your antenna. I have people put stuff on the dash near the antenna or try to sit in the walk way and interrupt the Sirius radio.