Ambient air temp sensor location?

[Madmudder]

Does anyone know where the ambient temperature sensor is mounted on a Yamaha FJR1300es?

 

[Queensland Ken]

Behind the rhs headlight panel.

It looks like a ring connector that isn't connected to anything, hangs in free air.

 

[Fred W]

It's #21 in the below diagram

 

[Madmudder]

Thank you guys. It seems to read warmer than it is around the bike so I suspected it was in the airbox, I am happy to hear it is in a relative ambient location.

 

[Bill Lumberg]

Mine reads 5 degrees high consistently. I think it's just the sensor, not the location.

 

[Madmudder]

Mine reads 5 degrees high consistently. I think it's just the sensor, not the location.

Bill, I am experiencing almost the same difference, so maybe it is more common than abnormality.

 

[Bill Lumberg]

Yep. Winter, summer, fast, slow, 4-5 degrees . I'm used to it. I'm just glad I have an ambient air temp reading.

 

[Lowcountry Joe]

I've yet to see a motorcycle air temp sensor worth a ****.

 

[Madmudder]

The question now begs how accurate is the coolant temp sensor?

 

[ionbeam]

The question now begs how accurate is the coolant temp sensor?

Sufficient.

Umm, since it is one of the core group of sensors that the ECU relies on I expect that Yamaha has specified an adequate part.

The ambient sensor is a different type sensor and on a motorcycle it's hard to find anyplace to put the sensor where it can make a valid free air measurement. If your FJR is parked in a garage where the floor isn't sun baked and the bike is shielded from the sun the ambient temp reading should be fairly accurate when you first turn the key on. Once the engine is started and the bike is in the sun and on pavement, all bets are off, it's just a trend indicator at that point.

 

[RossKean]

Does the FJR have two ambient temperature sensors???

I was looking at my 2007 FSM and found the one that is apparently associated with the FI. I believe that there is a second one (under the dash) that is a simple thermocouple (or similar device) that just provides ambient temperatures for the dash display. This is the one that is just a small device with what looks like a ring terminal on the end. No idea what the setup is for the Gen III. I find this to be quite accurate while the bike is moving but way off after parking the bike after running it.

It is in the middle of this pic from another thread; just beside the headlight adjuster knob.
From https://www.fjrforum.com/forum//index.php/topic/162993-whats-this-wire-do/?hl=%2B%2Btemperature+%2B%2Bsensor&do=findComment&comment=1226605

 

[Fred W]

I believe Ross is on to something. On 1st and 2nd Gen FJRs there is an "Intake Air Temperature Sensor", which screws into the air box.

On 2nd Gens, after they added the ambient air temp display in the instrument panel, they also added the little ring lug looking sensor for that function only.

On 3rd Gens I see only one "Air Temperature Sensor" which sends its signal to the ECU. I am assuming the ECU informs the instrument panel of the temperature as well as uses it for temp display on the dash gauge.

 

[RossKean]

In the Gen II manual, I did not find a specific reference to the temperature sensor in the photo in the FSM; probably part of the meter assembly and not a separate device. May be the same for Gen III?

 

[Madmudder]

So is it in the top of the fairing as indicated in the above diagram or in the air box or possibly in a totally different location on a Gen3?

Fred what is the source of the diagram you provided?

https://www.shopyamaha.com/parts-catalog/parts/street-mcy?ls=Street&dealernumber=#/Yamaha/FJR1300E_-_FJR13ESER_-_2014/ELECTRICAL_2

 

[danh600]

I actually find my sensor pretty accurate except when the engine is hot and the bike parked. When the bike is sitting with a cold motor or going down the road it's pretty close to correct. It's a 2013A.

After the bike has been run it causes a high reading (5-7 over) when I first start out again. Then it normalizes a few minutes into riding.

 

[majicmaker]

I agree, Dan. In about 90ish ambient temps, I'll stop at a convenience store and I'll see 108 on the gauge when I get back on. It goes back to normal once I get back on the road.

 

[lele]

my gen1 doesn't have a ambient temperature sensor but is equipped with an air conditioner..very confortable

 

[Madmudder]

my gen1 doesn't have a ambient temperature sensor but is equipped with an air conditioner..very confortable

Was that an option on the 01's? They did not make it to North America until 03's

 

[Fred W]

So is it in the top of the fairing as indicated in the above diagram or in the air box or possibly in a totally different location on a Gen3?Fred what is the source of the diagram you provided?

That was from the 2014 Factory Service Manual, electrical component location diagram. In another section of the manual where they tell you how to test the sensor, it indicates you would remove it from the windshield mechanism.

The same type of diagram for a 2nd Gen calls that sensor the Intake Air Temp Sensor, and shows it screwing into the airbox from under the back end of the gas tank, and describes removing it from the airbox for testing..

In the wiring diagrams for the 2nd Gen the Intake Air Temp Sensor is wired to the ECU, which makes sense. There is another item called "Thermistor" that goes to the multifunction meter, which must be the ring lug ambient temp sensor. There is no second "Thermistor" on the 3rd Gens, so it must share the same air temp sensor as the ECU.