Rear tire pressure monitor not working

[basmntdweller]

I was going through some of the menus on my new '09 today and noticed I wasn't getting any reading on the rear tire pressure. I initially noticed it at a gas stop so I figured I have to be moving but 50 miles later still no reading on the rear. Front seems fine although I haven't compared the display reading with an actual tire gage check.
Any possible simple fixes or just make a note of it for when I take it in for it's 600 mile check-up?

Thanks, Matt

[Jeremy Mitchell]

Let your dealer know, it is very likely that the battery died, or the transponder needs to be synced with the bike.

[basmntdweller]

I wondered if maybe the tire pressure was too low or something. I just checked it out and it was right on spec.
Thanks, Matt

[MrFurious]

Generally how accurate are everyone else's sensors?  Mine have consistently displayed 6psi low since the day I brought it home (i.e. tires gauge at 42psi but display shows 36psi for both).  This an indication of the sensors needing sync'd or possibly low batteries, or are the sensors just generally that inaccurate?

[Jeremy Mitchell]

Generally how accurate are everyone else's sensors?  Mine have consistently displayed 6psi low since the day I brought it home (i.e. tires gauge at 42psi but display shows 36psi for both).  This an indication of the sensors needing sync'd or possibly low batteries, or are the sensors just generally that inaccurate?

Have you checked your pressure gauge to make sure it is right?  Mine are dead on, but my first set of sensors was off by 1-2 psi.

[maxtog]

I was going through some of the menus on my new '09 today and noticed I wasn't getting any reading on the rear tire pressure. I initially noticed it at a gas stop so I figured I have to be moving but 50 miles later still no reading on the rear.  Any possible simple fixes or just make a note of it for when I take it in for it's 600 mile check-up?

Like Jeremy implied- no, there is no simple fix.  It is most likely the battery is dead or the unit is defective.  Either way, it is a big ordeal because the wheel has to be removed and the tire has to be removed.

You don't have to be moving to get a reading.   But you have to move some before you will get a reading.  On mine, I usually have a reading by the time I have moved a few hundred feet.

[lt1]

In general the TPS is quite accurate.  It is temperature compensated to about 65F.  The compensation is approx 1psi/10F.  Try a search for the chart, IIRC it has been posted since the restart.

[R Nelson]

My rear TPS is out as well.  I got the low battery warning for awhile, so I'm pretty sure the battery just ran out of juice.  This happened shortly after I installed new tires, so I wasn't in the mood to pull the rear back off, so I've been dealing w/o the rear readout for awhile.  I will figure a way to replace the battery on it when the tire is ready for replacement.  I'll have to do a little research on how to do this because I know it's not a simple swap.

[So Cal Joe]

I just had my front sensor replaced on my 09 under warranty, it just showed ---- ,Dealer told me the batteries in the sensor is guaranteed for 5 years so take it back to the dealer, changing the battery in the early units can be done but it's not an easy job.

[basmntdweller]

I just had my front sensor replaced on my 09 under warranty, it just showed ---- ,Dealer told me the batteries in the sensor is guaranteed for 5 years so take it back to the dealer, changing the battery in the early units can be done but it's not an easy job.

Good to know the battery is warrantied. I figured they would warranty the sensor but not that battery. Since mine has been sitting in a crate for years, I figured it just went dead and it wouldn't be covered. I would have just done without until I needed a tire. Since I only have 200 miles on it so far, a new tire is a long ways off.

Thanks, Matt

[maxtog]

Good to know the battery is warrantied. I figured they would warranty the sensor but not that battery. Since mine has been sitting in a crate for years, I figured it just went dead and it wouldn't be covered. I would have just done without until I needed a tire. Since I only have 200 miles on it so far, a new tire is a long ways off.

It is very unfortunate this technology requires a battery at all.  Certainly one could design something that would convert the mechanical energy of the wheel turning into enough power to operate the unit.

[VirginiaJim]

My RAV4 TPS uses the ABS wheels to determine a problem with air pressure in the tires.  Downside is it can't tell you which one is low, but it's not that big of a deal to check them all.

[C1xRider]

Generally how accurate are everyone else's sensors?  Mine have consistently displayed 6psi low since the day I brought it home (i.e. tires gauge at 42psi but display shows 36psi for both).  This an indication of the sensors needing sync'd or possibly low batteries, or are the sensors just generally that inaccurate?

Mine read about 4-5 psi low.  Always have, but they seem consistent about it.

[C1xRider]

It is very unfortunate this technology requires a battery at all.  Certainly one could design something that would convert the mechanical energy of the wheel turning into enough power to operate the unit.

I've thought about that too, but once the wheel is spinning, all you have is basically centrifugal pressure, which is static at a given speed.  It would be a technology challenge to turn that into useful voltage and current to power the sensor.

I would have expected them to have some form of internal power switch that once the centrifugal pressure is present, would close to activate the power to the sensor.  Seems that would save the battery by only powering it during operational use.  It would also explain why you have to be moving to get a reading.  However, I don't think these have something like that, and that they are just very cheaply made.

One thing I don't get is the cost.  I bought new TPMS for my 2005 GMC at NAPA for about $40 each for my winter wheels.  They work when the thing is parked, and are pretty accurate.  They also work at temps down below zero.  These things on the bike sell for hundreds, and barely work at all. 

[maxtog]

I've thought about that too, but once the wheel is spinning, all you have is basically centrifugal pressure, which is static at a given speed.  It would be a technology challenge to turn that into useful voltage and current to power the sensor.

Yep, I was thinking the exact same thing.  There is nothing "relative" to the spin inside the wheel that could be used to generate continuous motion.  Even gravity would malfunction, due to centrifugal force. Still, there must be a way.

I would have expected them to have some form of internal power switch that once the centrifugal pressure is present, would close to activate the power to the sensor.  Seems that would save the battery by only powering it during operational use.  It would also explain why you have to be moving to get a reading.  However, I don't think these have something like that, and that they are just very cheaply made.

Exactly!  When I first got the bike, I was very excited about the TPS.  As soon as I realized I had to be MOVING first I thought  "WTF???  So I have to get completely geared up, plugged in, and leave the house, and then two blocks away find out I have to go back to the house, de-gear, de-plug, and fill up a tire?"  And then read about all the dead batteries and guess it does not have a switch at all.  So exactly what is the point of ONLY working after the bike is moved?

One thing I don't get is the cost.  I bought new TPMS for my 2005 GMC at NAPA for about $40 each for my winter wheels.  They work when the thing is parked, and are pretty accurate.  They also work at temps down below zero.  These things on the bike sell for hundreds, and barely work at all. 

Supply and demand.   Kawasaki will charge whatever they think they can get away with... there is no competition.

[B.D.F.]

Er, I think you guys are reinventing the wheel here.

First of all, the sensors do have a switch in them and it works on centripetal force. As the motorcycle spends much more time being stopped than it does being ridden, turning the sensor on and off makes sense to increase battery life.

As far as doing something to eliminate the battery, that would not be a problem but every other solution I can think of would be more complex, expensive and take more maintenance than the battery powered method already used. Just a few thoughts on how to do this:

You could use a spring and a weight with a magnet inside a tube surrounded by a coil, all of which would be mounted inside the wheel. As the wheel turned, the weight would move back- and- forth making a crude but effective generator. This idea is from 'self- winding' electric watches from 50 years ago. You could also use a weight and spring in a tube in the same method except to have it use an escapement to move a wheel which would contain the generating section. This idea from ancient clocks coupled with 1900 era electrical generation. You could put a slip ring on the outside of the wheel and simply power the sensors by running a wire back to the main harness. This is an idea dating back to the mid- 19th century electrical generation. You could mount a small spur gear on the axle of each wheel and have that engage another gear on the inside of the wheel to turn a small generator. This idea from 18th century water wheel apparatus. Finally you could simply put some magnets on the wheel's axles, and put a wire winding (a coil) on the inside of the wheel; this makes a generator and would easily generate sufficient energy to power any number of tire pressure sensors.

As I said, all more expensive and complex than the method already used. But Rube Goldberg would be proud.... 

Brian

Yep, I was thinking the exact same thing.  There is nothing "relative" to the spin inside the wheel that could be used to generate continuous motion.  Even gravity would malfunction, due to centrifugal force. Still, there must be a way.

Exactly!  When I first got the bike, I was very excited about the TPS.  As soon as I realized I had to be MOVING first I thought  "WTF???  So I have to get completely geared up, plugged in, and leave the house, and then two blocks away find out I have to go back to the house, de-gear, de-plug, and fill up a tire?"  And then read about all the dead batteries and guess it does not have a switch at all.  So exactly what is the point of ONLY working after the bike is moved?

Supply and demand.   Kawasaki will charge whatever they think they can get away with... there is no competition.

[stevewfl]

Er, I think you guys are reinventing the wheel here.

First of all, the sensors do have a switch in them and it works on centripetal force. As the motorcycle spends much more time being stopped than it does being ridden, turning the sensor on and off makes sense to increase battery life.

As far as doing something to eliminate the battery, that would not be a problem but every other solution I can think of would be more complex, expensive and take more maintenance than the battery powered method already used. Just a few thoughts on how to do this:

You could use a spring and a weight with a magnet inside a tube surrounded by a coil, all of which would be mounted inside the wheel. As the wheel turned, the weight would move back- and- forth making a crude but effective generator. This idea is from 'self- winding' electric watches from 50 years ago. You could also use a weight and spring in a tube in the same method except to have it use an escapement to move a wheel which would contain the generating section. This idea from ancient clocks coupled with 1900 era electrical generation. You could put a slip ring on the outside of the wheel and simply power the sensors by running a wire back to the main harness. This is an idea dating back to the mid- 19th century electrical generation. You could mount a small spur gear on the axle of each wheel and have that engage another gear on the inside of the wheel to turn a small generator. This idea from 18th century water wheel apparatus. Finally you could simply put some magnets on the wheel's axles, and put a wire winding (a coil) on the inside of the wheel; this makes a generator and would easily generate sufficient energy to power any number of tire pressure sensors.

As I said, all more expensive and complex than the method already used. But Rube Goldberg would be proud.... 

Brian

hmmm as long as no one is jacking up the perfect  KiPass  system....continue efforts on the wheel 

[VirginiaJim]

One thing I don't get is the cost.  I bought new TPMS for my 2005 GMC at NAPA for about $40 each for my winter wheels.  They work when the thing is parked, and are pretty accurate.  They also work at temps down below zero.  These things on the bike sell for hundreds, and barely work at all. 

My daughters own Nissan vehicles and both of them have had the cold issue (complain they aren't working) with the sensors.  We've had to replace one sensor (damaged valve) and it was $150 with the registration and all.  Still, it's a bit cheaper than ours.

[sycamoredave]

My sensors both went out last fall.  This spring I took it to the dealer, who claimed they were damaged by the thimble full of Dynabeads we put in the year prior.  The TPMS issues actually predated the beads, so that was pretty much bull.  The multi-hundred dollar solution to fix seemed rather obscene to me.  My solution has been to turn the system off.  I have a $2 tire gauge that works fine.  The TPMS was never accurate anyways.  I wish KIPASS fixes were that easy!   

Ride safe...
Dave

[oldnslo]

I have had 6 tps replaced under warranty on my 2009,dead batteries.latest ones have lasted about 15k with no failures yet. I bought the extended warranty mainly for this.