Outside air temperature sensor?

[TerraPhantm]

This might be actually a good explanation, I am thinking that maybe my car didn't have one from factory although my e46 doesnt seem like its obc was retrofitted and it does have auto climate control.

If you have climate control you should have it. 318s might simply have it in a different spot

[jhyan]

After replacing the sensor 3 times over 5 years, I mounted the last one way up inside the inside of the bumper. Now the wife is no longer able to yank it off by running into parking lot curbs.

How does it work up in the bumper? I'm thinking of doing this.

[BMWoW]

How does it work up in the bumper? I'm thinking of doing this.

Since it is still outside, it functions the same.

Sent from my iPhone using BF.com

[danewilson77]

How does it work up in the bumper? I'm thinking of doing this.

It is an air ambient temperature sensor.

Sent from my Thunderbolt using BF.com

[ZeeZoo]

They are only $40 for them.

I got stealership'd

Zip-tied it to the remaining inner wheel fender cover:

I just fixed this in my car last month. -40 degrees means you are missing the sensor, +122 means the wires are short circuiting. I paid $92 dollars at the dealer, do yourself a favor and just order it from a reputable site online and wait for shipment. Not having it won't hurt your car so it's not an immediate fix.

[ECSTuning]

^ouch! HERE is a link to the sensors, both the OEM and aftermarket are about half the dealership cost.

James with ECS

[affuman]

Great, informative thread!

Over the last year or so, my temperature has been consistently reading 10 degrees F over what it actually is (as reported by store signs, etc). Any ideas why, before I go digging under the wheel well?

Thanks in advance!
-A

[Teraxx]

Great, informative thread!

Over the last year or so, my temperature has been consistently reading 10 degrees F over what it actually is (as reported by store signs, etc). Any ideas why, before I go digging under the wheel well?

Thanks in advance!
-A

I have the same exact problem, but in reverse. A consistent outside temp reading 10 degrees below what it actually is outside, so it displays 40 F when it's really 30 F. I'm thinking that external probe/sensor has to be the answer to this problem.

[marknfw]

Mine has been reading -35 for the past few weeks. I guess it probably means the same as the -40's? The car is a 1999 328ic.

edit: the display is not on the center dash, it's on the check control display

[Edlvrt]

Mine has been working fine for the most part, but every few days, it will show 37*F when the air temp is 60+. Bad sensor?

[Edlvrt]

Mine has been working fine for the most part, but every few days, it will show 37*F when the air temp is 60+. Bad sensor?

[Frozen258]

I read this post and decide that my dash works not good. All the time it show +50C/122F. I replaced new wires from dash and get same +50/122. Already replaced 2 sensors and no one works. Yesterday i saw interesting thing... My car was standing on the sun all day and it showed +38C, but then i take it go garage it starts showing : 38 37.5 36.5 35.5 34.5 34 and +50 again. I get car outside again and it shows +37... Temperature shows only from +34C/93F. If i remove wires from dash i get +50 anyway than i should get -40. But then i connect + and ground wires together it shows -40C.

[Thaniel]

I read this post and decide that my dash works not good. All the time it show +50C/122F. I replaced new wires from dash and get same +50/122. Already replaced 2 sensors and no one works. Yesterday i saw interesting thing... My car was standing on the sun all day and it showed +38C, but then i take it go garage it starts showing : 38 37.5 36.5 35.5 34.5 34 and +50 again. I get car outside again and it shows +37... Temperature shows only from +34C/93F. If i remove wires from dash i get +50 anyway than i should get -40. But then i connect + and ground wires together it shows -40C.

To test it just put a variable resistor between the 2 wires and change the resistance. It will move slow but the value will change. This way you can test to see if your wiring and IKE are working.

[Frozen258]

what variable resistor i should buy? any links please

[Redy]

I read this post and decide that my dash works not good. All the time it show +50C/122F. I replaced new wires from dash and get same +50/122. Already replaced 2 sensors and no one works. Yesterday i saw interesting thing... My car was standing on the sun all day and it showed +38C, but then i take it go garage it starts showing : 38 37.5 36.5 35.5 34.5 34 and +50 again. I get car outside again and it shows +37... Temperature shows only from +34C/93F. If i remove wires from dash i get +50 anyway than i should get -40. But then i connect + and ground wires together it shows -40C.

Hi

I've got the same problem, after outside temperature drops below +14°C i get +50°C. Everything above +14°C works OK.
No solution found Yet.

[bin01123]

If it says -40 then it's effectively an open circuit. It's likely one of the following four situations: - a wire is broken - the probe is broken - the probe is disconnected - the probe is gone outright (run over any curbs lately?) Your first step will be a visual inspection of the temperature probe - it should look like my second photo, above. Second step will be to disconnect and reconnect the probe (in case it's just loose) and see if anything changes. Third step will be to remove the probe and put a short wire jumper over the terminals in the probe connector. If the wires are good, the temperature will read +122 due to the closed circuit. If there's a break in the wire somewhere, the temperature will read -40 due to the open circuit.

Great write up

[limasp]

I had the sensor on mine ripped off once so I relocated it in behind the front fender liner. Now its well up and away from moisture and other problems.

[Edmonton122]

Ok, back from the dead...
I have a 1998 E38
I've looked under both sides and can't find any blue wires. And I've looked everywhere.... I'm so confused (and uncomfortable). The A/C is fighting this like a prick because it thinks it's -40c and it's actually +35c.
Any other ideas as to where I could look for the wires??

[Chris951]

They are in the wiring harness for the drivers side fog light. All you have to do is peel back the electrical tape and there will be two blue wires in there..... not that hard.....

[andyleonard]

Bodyshop took mine off for painting and reinstalled it with one of the tiny contact pins bent over. I straightened the pin and all was good. Check the contacts before buying parts.

[Edmonton122]

They are in the wiring harness for the drivers side fog light. All you have to do is peel back the electrical tape and there will be two blue wires in there..... not that hard.....

Well, I've followed the for light wires all the way up to the fender well. No blue wires. Does anyone know where their final termination point is?? As in do they plug straight into the back of the climate control unit in the car??

[balidawg]

Just want to add another possible cause to this thread that had me perplexed before I figured it out. The horn and temp sensor have nearly identical connectors that will fit if forced! So check if they got swapped if the wire colors don't seem correct. This happened to me recently.

A truck backed into my front bumper and damaged it. While the car was at Caliber Collision having a new bumper installed they somehow swapped the horn and temp sensor plugs. When I got the car back the SES light was on because of the sensor's apparent use by the DME. I read the codes with PA Soft BMW Scanner 1.4 and noticed the IKE error regarding the ambient air temp sensor. I also noticed the cluster displayed -40C. My car is a 2004 330Ci with MS45.1 DME.

While working on the problem I saw the temp sensor plug didn't fit quite right and was pushed on really hard, plus the wire colors didn't match those on pins 1 and 2 of the instrument cluster connector. After probing the wires, reading the WDS, and thinking about it for a few days I suddenly thought maybe the wrong plug was on there and went back to look at the car. That's when I noticed the correct colored wires going to the horn. Bingo!

[Rockyview]

Well, I've followed the for light wires all the way up to the fender well. No blue wires. Does anyone know where their final termination point is?? As in do they plug straight into the back of the climate control unit in the car??

Old thread but I have the exact same question and I also live in Alberta. Common problem for us Canucks I guess, eh. So, does anyone know where to look to find the source of these wires?

Thanks!

[moapys]

Old thread but I have the exact same question and I also live in Alberta. Common problem for us Canucks I guess, eh. So, does anyone know where to look to find the source of these wires?

Thanks!

+1 ...I have no "remains" of either the sensor itself, or shards of its ripped-out socket/wiring... Might anyone have '03-330i details for which bumper wiring spur that contains the wire pair (e.g. running lamp, etc)? THX

[disccooker]

Old thread but immediately after coding my E91 today my temp sensor is reading 90 degrees f
Should I restore backup?