Pressure control sensor

[harpo]

My check engin light came on on my 03, the code#was 31. I took it in to the dealership where they found the pressure sensor that senses the altitude pressure is reading 736Kpi at 1000 feet where it should show 97Kpi. Now this is where it gets wierd, they ordered a new one and it to reads the same. The engin light went out and everything reset, but when the tec called Yamaha's tec support they never would say why my 03 with the same sensor number and all as any outher FJR reads so much higher than any outher.

Does any one know if some of the very first FJRs that made it into the US was European models and if so could they be reading on a totaly differant pressure scale.

 

[RossKean]

My check engin light came on on my 03, the code#was 31. I took it in to the dealership where they found the pressure sensor that senses the altitude pressure is reading 736Kpi at 1000 feet where it should show 97Kpi. Now this is where it gets wierd, they ordered a new one and it to reads the same. The engin light went out and everything reset, but when the tec called Yamaha's tec support they never would say why my 03 with the same sensor number and all as any outher FJR reads so much higher than any outher.Does any one know if some of the very first FJRs that made it into the US was European models and if so could they be reading on a totaly differant pressure scale.

736 sounds like mm of mercury - traditional barometer.

 

[3dogs]

Your situation sounds familiar. A dealer reads a code from an ECU and on that basis replaces a sensor—but the new sensor acts the same, i.e., doesn’t read correctly and/or sets the same fault code. The fault codes are only a place to start the diagnosis of any ECU/Engine performance problem. For the BARO (air pressure) sensor they should have checked the 3 wires that connect it to the ECU. 1) ground to the ECU (and the ground from the ECU to the battery), 2) the power wire to the sensor (usually 5 volts) and 3) the sensor’s signal wire to the ECU. Without verifying these inputs/outputs replacing the sensor based on a code is a crap-shoot.

Automotive repair shops/dealerships went through this learning curve 15 years ago (some still haven’t got there). Motorcycle dealerships are generally behind in their ability to deal with EFI systems. Surprisingly enough, independent auto repair shops (the good ones) are the best at diagnosing computer related issues because they can’t just swap ECUs or sensors to see if that fixes a problem.

 

[Constant Mesh]

On the Gen I models there are two identical air pressure sensors -- the map sensor sampling the intake pressure and the atmospheric sensor under the seat.

You can check one sensor against the other when the engine's not running -- they both should indicate the atmospheric pressure.

 

[harpo]

Thanks for the info, You may be right.

 

[DonRed7]

I think the reading may be in mbar which makes sea level about 998 mbar and absolute vacuum 0 mbar (outer space). I work on vacuum packaging machines and 1000ft above sea level might just be close to 800 or so as it is a descending #.

Thats all i'm saying bout that....

-Don