Possible bad speed sensor?

[James Guillaume]

I'm very familiar with these sleds, but I have never seen nor can find any other forums about a bad speed sensor. I have an 06 which at the end of last season started to have the speedometer read slower than the actual speed. (GPS confirmed) It would drop off pretty badly over 40 mph and just read slower, and never display much more the 60 on the dash even if I was going 90. Lower chain case bearing as well as driveshaft bearing was done due to failure at the very first ride that season. The speedometer issue didn't show up until later. I never dug into the issue as it arose late season and I parked it for the year. I went to ride last weekend and about 25 minutes into the trip the speedometer just started reading zero. I would sometimes see 1 mph. Eventually, codes 84 and 42 came up, which I know mean that there is no input from the speed sensor. Bearings all look good. The sled has 10,000 miles on it, what are the chances of it actually having a bad speed sensor? I can switch the one from my dad's Attak but before I do I wanted to just check and see if this ever happens or if I should expect more problems. Thanks!

 

[MrSled]

I'm very familiar with these sleds, but I have never seen nor can find any other forums about a bad speed sensor. I have an 06 which at the end of last season started to have the speedometer read slower than the actual speed. (GPS confirmed) It would drop off pretty badly over 40 mph and just read slower, and never display much more the 60 on the dash even if I was going 90. Lower chain case bearing as well as driveshaft bearing was done due to failure at the very first ride that season. The speedometer issue didn't show up until later. I never dug into the issue as it arose late season and I parked it for the year. I went to ride last weekend and about 25 minutes into the trip the speedometer just started reading zero. I would sometimes see 1 mph. Eventually, codes 84 and 42 came up, which I know mean that there is no input from the speed sensor. Bearings all look good. The sled has 10,000 miles on it, what are the chances of it actually having a bad speed sensor? I can switch the one from my dad's Attak but before I do I wanted to just check and see if this ever happens or if I should expect more problems. Thanks!

I have never seen it happen but sure sounds like a good possibility.

 

[steiner]

Your dad's Attak will have the exact same speed sensor.
I would look at the ground blocks first tho. These blocks are known for causing strange electrical issues.

 

[msgt van]

Gear tooth sensors of that type typically work, then quit altogether.