In-dash air temperature sensor display

[GRHorst]

I've noticed that the in-dash air temperature sensor seems to be consistently 2-5 degrees above the ambient air temperature. I was wondering if there is a way to calibrate this sensor and if other persons have noticed this difference?

It could be different for each bike. Having messed with electronic temperature sensors using an Arduino single-board computer, I have learned that temperature sensors can vary significantly. That's why I'm wondering if a calibration is possible?

[Peter Aawen]

There's no calibration option readily available GR.... sorry!

This gauge & it's 'not accurate' readings is a fairly frequently discussed issue, and part of the problem is that many people erroneously think of it as an ambient air temp gauge - it's NOT! . It's simply a display of the temp detected under the Tupperware & on top of the engine (think added radiant AND heat soak issues! ) that's used by the ECU in deciding how best to run the engine, only some BRP marketing wunderkid thought it'd be cheap way of adding a feature to Spyders without actually doing much!

Anyhow, check the thread linked below out, it's fairly recent & based upon a 2021 Spyder, but most of it applies regardless.

https://www.spyderlovers.com/forums/...uge%3B+ambient

[trikermutha]

You could move the sensor but see no need to do that . As mentioned by Peter it is also used by the ECU .

Just ignore the temp reading and ride more.

[LongIsland]

3 things I ignore on my 2014 RTL dash display: the temperature, the time and the mph. All 3 are incorrect, so I look at my GPS for accurate readings.

Ride Safe!

[hypurone]

3 things I ignore on my 2014 RTL dash display: the temperature, the time and the mph. All 3 are incorrect, so I look at my GPS for accurate readings.

Ride Safe!

This can be corrected within BUDS if you have it.... Just zero out the speedometer "correction" factor setting.... Makes me wonder why the hell they have it in there when it is incorrect!

[GRHorst]

Thanks for the info. My MPH is quite close to both GPS speed and the "Your speed is" radar indicators on the side of the road. Usually of by only 1 mph.

Not sure why BRP thinks I want to know the temperature detected under the "Tupperware on top of the engine". But ... OK ... now I know what it is. If they want to display in the dash I think they would want to have a second sensor located where the ambient temperature can be sensed accurately.

[chunkmonk]

...
Not sure why BRP thinks I want to know the temperature detected under the "Tupperware on top of the engine"...

GR - I think the point that Peter was making was that it was designed as a sensor temp used as a runnable parameter for the ECU (making quasi-AI decisions about how to run the motor), and that marketing and sales got hold of the fact that the sensor was tracking this data point and thought that they could turn it into a "sales pitch" to customers that the Spyder can tell you the "ambient temperature" (which it, in fact, cannot).

[GRHorst]

GR - I think the point that Peter was making was that it was designed as a sensor temp used as a runnable parameter for the ECU (making quasi-AI decisions about how to run the motor), and that marketing and sales got hold of the fact that the sensor was tracking this data point and thought that they could turn it into a "sales pitch" to customers that the Spyder can tell you the "ambient temperature" (which it, in fact, cannot).

Sound like a likely scenario. I liked the temperature display on my Goldwing which seemed to be fairly accurate. Oh well ... now I know.

[AeroPilot]

While touring we often compare data as a way to stay alert on long trips to family in Kansas or around the mountains in Colorado and New Mexico. Although my wife rolls her eyes at my data compulsion, she will share via our headsets that her 16 F3T temp reading is usually the same or within a degree of what I say my 15 RT temp is showing. We have learned that our readouts are usually 5 to 7 degrees higher than the posted "Bank sign" readings in the towns we pass through. So my mental math tells me when seeing a temp of 100 F that it's actually 93 or so, and time to stop and cool down or recharge the cooling vests.

I'm actually impressed that while not accurate for ambient temperature, the Can-Am temp sensors are rather precise in their input to engine/fuel programming. JMHO

[IdahoMtnSpyder]

This gauge & it's 'not accurate' readings is a fairly frequently discussed issue, and part of the problem is that many people erroneously think of it as an ambient air temp gauge - it's NOT! . It's simply a display of the temp detected under the Tupperware & on top of the engine (think added radiant AND heat soak issues! ) that's used by the ECU in deciding how best to run the engine, only some BRP marketing wunderkid thought it'd be cheap way of adding a feature to Spyders without actually doing much!

Sorry to disagree with you Peter, but it is in fact an ambient temperature sensor. It is a single unit and is both ambient temperature and ambient pressure sensor providing data to the ECM to control engine operation. Joel and I discuss it starting here, https://www.spyderlovers.com/forums/...=1#post1624143.

I enlarged the air tunnel hole below the sensor on my RT. The temp on the gauge is close to T & T signs. The only thing I do not know is if, with the larger hole, the air pressure that is sensed is incorrect. I've often wondered if that has contributed to my lower than normal gas mileage. It really would be best to not muck with the sensor since its output is a critical parameter in controlling the engine.

My conjecture is the location shown on one of the engine diagrams showed where the sensor was originally designed to be located, but by the time the 1330 went into production its location was changed but the diagram was not. Another diagram shows it in the air tunnel and that is where I found it.

[IdahoMtnSpyder]

Not sure why BRP thinks I want to know the temperature detected under the "Tupperware on top of the engine". But ... OK ... now I know what it is. If they want to display in the dash I think they would want to have a second sensor located where the ambient temperature can be sensed accurately.

I cannot stress strongly enough that understanding is flat out incorrect! See my post above and the one I link to.

[Bfromla]

Just ignore the temp reading and ride more.

Nanny will let you know when too hot to ride & yes can set off just parked out in sun
has happened around here anyway.

[Peter Aawen]

I cannot stress strongly enough that understanding is flat out incorrect! See my post above and the one I link to.

Sorry Idaho, but ANY temperature sensor that's under the tupperware &/or on top of the engine is not going to show you a similar 'ambient temperature' to the temperature your local Bureau of Meteorology (BOM) will tell you is that day's ambient temperature!

Your earlier post where you write "It is a single unit and is both ambient temperature and ambient pressure sensor providing data to the ECM to control engine operation" explains quite clearly what the info from that sensor is essentially doing/for... it's all in this bit - "....providing data to the ECM to control engine operation".... THAT bit is essential to the proper operation of your engine, ie. providing the ECM with the necessary info on the air that it's about to use, which is the air that's actually been exposed to the direct heat and radiated heat experienced under the tupperware & on top of the engine before it goes into the engine be utilised efficiently in the combustion process; and given this fact that you've highlighted once more, to expect the temperature shown on your dash to accurately do anything else, like informing the rider of what the still air temp is in the way the BOM reports on the ambient temp inside a Stevenson Screen protecting it's sensor from any direct heat & radiated heat in a location off somewhere else that's relatively protected.... is surely somewhat unreasonable, isn't it??

The BOM's ambient air temp & the Spyder's under tupperware & on top of the engine air temps have two completely different purposes! As many have found & commented, the BOM's reported ambient air temp and the temperature derived from the sensor that is under your Spyder's tupperware & just above the heat generating cylinders of your Spyder's engine are quite likely NEVER going to be the same - this is because the BOM is telling you the temperature as one part of a measure of YOUR personal comfort; while the DASH is telling you the temperature being passed to your Spyder's ECM as part of the necessary/essential info for it to operate properly given the air it's sucking in! . And YES, mucking around too much with the positioning of your Spyder's air sensor in order to get the dash display closer to the BOM's stated ambient is quite likely to impact on how well your Spyder engine runs.... but it IS your Spyder & your engine, so you can do what you will with it. In the meantime, unless/until you do something that may or may not harm the performance &/or longevity of your Spyder, the temperature reported on the dash is EXTREMELY UNLIKELY to be all that close to the BOM's reported ambient temp, cos THAT'S NOT WHAT THE SPYDER'S SENSOR IS COLLECTING THAT TEMPERATURE/PRESSURE INFO FOR and to show it &/or read it as something it's not is misleading at the least!

[IdahoMtnSpyder]

This can be corrected within BUDS if you have it.... Just zero out the speedometer "correction" factor setting.... Makes me wonder why the hell they have it in there when it is incorrect!

I just checked my RT with BUDS (not BUDS2). What I find is the analog speedo needle can be adjusted by 1 point at a time. But that would make a correction that is constant and not proportional to speed so a 1 point clockwise will show 41 mph instead of 40 and 71 mph instead of 70. The digital display, while parked, still showed zero, so I don't believe the speed correction owners want can actually be accomplished except by a rear tire change.

Keep in mind International regulations under the United Nations prohibit any speedometer from showing a speed less than actual. The error for showing faster than actual is permitted to be as much as 10%.

[IdahoMtnSpyder]

Sorry Idaho, but ANY temperature sensor that's under the tupperware &/or on top of the engine is not going to show you a similar 'ambient temperature' to the temperature your local Bureau of Meteorology (BOM) will tell you is that day's ambient temperature!

Why do you keep saying the AAPTS is on top of the engine? It is not. It's in the intake air tunnel in the frunk, at about 6 to 9 inches or more in front of the radiator where the incoming air has not yet been heated by the engine and where it is shielded from radiant engine heat. It is under the frunk tupperware but the only non ambient air heat it sees is the sun heating the top of the frunk. My 2013 went into limp mode one time from the sun beating down on the frunk (RT was parked and engine cool) and the ambient temp on the gauge went above 115° F. The only sensor that is above the engine is the MAPTS (manifold absolute pressure and temperature sensor) and it's in the air box and not directly exposed to engine heat emitting surfaces.

The 2013 and 2014 service manuals explicitly say the AAPTS measures the atmospheric air temperature and pressure. Since it measures the atmospheric temperature it makes sense to leech the readings from it to display as ambient temperature the rider is exposed to. The only reason it doesn't more closely reflect outside air temp is because, in my judgment, not enough air is allowed to flow past the sensor (there's a foam screen on it) to offset the radiant heat off the topside tupperware of the frunk. My mod allows more air to flow past the sensor so it reads outside air temp more accurately.

What we haven't seen anyone mention is how much the cluster outside air temp reading varies from T & T signs when they are riding in cold weather, say under 50° F. I would be somewhat surprised if it read higher than the T & T signs in that case.

[Peter Aawen]

Why do you keep saying the AAPTS is on top of the engine? It is not. It's in the intake air tunnel in the frunk, at about 6 to 9 inches or more in front of the radiator where the incoming air has not yet been heated by the engine and where it is shielded from radiant engine heat.....

Regardless of where your AAPTS is (& I've seen them in quite a few different places - and my 2013 RT doesn't now nor ever has had an air intake tunnel in the frunk!! ) it's almost certainly going to be under the tupperware somewhere and very likely higher than the bulk of the engine & the heat it generates that then gets captured in that insulated case under the tupperware.... so answer me these - Is the sensor inside/under the tupperware ANYWHERE?? Is it at a higher level than the engine ANYWHERE?? If the answer to either &/or both is YES, then that sensor IS subject to the radiant heat from the sun on the tupperware; AND subject to heat soak and radiant/reflected heat from everything else under the tupperware, including the engine, the frame, and even the patch of road you might happen to be driving/riding over!

If you want to test this (as I have already done on a few Spyders) ride your Spyder for a while then park it in a sheltered position in still air; extend the wires so you can pull the sensor out; & hang it on the shady side of the Spyder to at least partly emulate the way the BOM measures ambient temperature - and in a few minutes the temperature shown on the dash display will probably get a whole lot closer to the BOM ambient temp; but then the moment you put that sensor back under the tupperware ANYWHERE, even if you put it in the frunk (as I did for a couple of tests after doing that first test above! ) then if the Spyder has been run that day at all I'd suggest the temperature displayed on the dash will most likely start to go up again....

So Idaho, why do you keep insisting that this sensor, which you admit that you yourself have modified in order to try and get it to be more accurate/clos err to 'ambient' and that BRP says is there to "measure the air pressure & temperature going into the engine" in order to help it run properly is truly reflecting 'ambient temperature' as you feel it??? .... altho I guess you could say it is sorta ambient, if you consider only the raised temperature under the tupperware & above the engine (even if it's juuust a little higher and a few or more inches forward of the engine! ) then it might be safe to call it 'ambient temperature for the air under the tupperwear & above the engine', but it's NOT the same 'ambient temperature' that your local Met Bureau will publish/broadcast; so as I've stated before, for those questioning why it's not 'more accurate', it's best not to even consider it that way.... . At least by not considering it a true reflection of the BOM ambient temperature then most will readily see that the dash display IS NOT LIKELY TO MATCH THE BOM's PUBLISHED/BROADCAST AMBIENT TEMPERATURE OFTEN IF AT ALL!!

And if by T & T signs you mean the signs on roadsides & buildings that might be showing the BOM published/broadcast temp for that time, or equally might be a remote display of the el-cheapo Dodgy Bros weather station, or possibly even someone's home Weather Station of dubious accuracy, then I'll tell you now that I've NEVER seen one of those signs displaying a temp within 5° C of the temp shown on my dash - at least for me here in Oz, even when I'm riding in the snow of our Snowy Mountains, the dash display is ALWAYS something near or above 5° C higher than the temp displayed by those signs, and not always varying by the same amount either....

But if you want to believe that your dash temp display is more accurate than anyone else's Idaho and that it gets close to or matches the BOM published/broadcast ambient temperature, I'm OK with that, it's your Spyder - I still don't believe it reflects true ambient temp and probably won't until I see it/experience it in person, but for all those OTHER people asking why their Spyder's dash temp display almost invariably shows a higher temp than what their local weather station/BOM is telling them the ambient temp might be, it's simply because the sensor for the Spyder is NOT in a sheltered and sheilded Stevenson Screen/instrument shelter somewhere, it's UNDER THE SPYDER's TUPPERWARE & SUBJECT TO RADIANT HEAT FROM SUN HEATING THE TUPPERWARE & EVERYTHING UNDER IT AS WELL AS ANY RADIANT HEAT, HEAT SOAK RISING FROM THE ENGINE, & REFLECTED HEAT FROM THE ENGINE AND EVERYTHING ELSE THAT MIGHT HAPPEN TO BE LOWER THAN THE TUPPERWARE & BELOW THE LEVEL OF THE SENSOR AT THAT TIME! - So if any of you (besides Idaho) are confused, it's simply best NOT to ever consider that dash displayed temperature as the true 'ambient temperature', cos it's never likely to reflect the 'ambient temperature' shown from any other source, including that shown by your BOM or equivalent!

[Mikey]

Gess, if I was a moderator, I would think this is getting pretty heated, and ready to be FIXED!! Take a breath and step back boys!! The long and short of it is just read the darn temp and KNOW it's off, and ride on and enjoy the day. There's nothing you can do for the issue that won't muck up something else! Chill!!

[GRHorst]

Yikes, I had now idea I could instigate such a long discussion when asking about the in-dash air temperature sensor!!

As Mikey said .... RIDE ON !

[Snowbelt Spyder]

This can be corrected within BUDS if you have it.... Just zero out the speedometer "correction" factor setting.... Makes me wonder why the hell they have it in there when it is incorrect!

Idaho, and whoever else is interested since it came up in here - It appears with a Megatech License. Otherwise it is hidden. That calibration factor you see comes from the factory and was the same number in most of the BUDS sample files for Spyders. The ATVs and SxS also have correction factors but using a different number. This 1868 number works out to around 2.8%. Causes it to read high, but that seems to be the intent. If ya’ll are ever in the neighborhood…..

[chunkmonk]

...
Keep in mind International regulations under the United Nations prohibit any speedometer from showing a speed less than actual. The error for showing faster than actual is permitted to be as much as 10%.

And we wouldn't want to upset the United Nations, now, would we?