Threaded Mode | Linear Mode

Starlight · 04-20-2018, **(Subject: I found the Ambient Air Temp Sensor! 2008 ProStar... )**

(04-26-2017 )Brock Wrote: Let me dumb this up a bit....

Are you saying the outside air temp sensor.... the one that shows on your dash how hot it is outside, is also tied into how the engine runs?

Yes sir. I know a local guy with a 2013 kw that ran fine and with no warning and engine lamps on derated on him. Being under warranty at the time he took it to kw and all they found was a defective ambient air temp sensor in his mirror. They replaced it and the derate disappeared. Gotta love that.

Brock · 04-20-2018, **(Subject: I found the Ambient Air Temp Sensor! 2008 ProStar... )**

Is that what this is?

74bassman · 04-20-2018, **(Subject: I found the Ambient Air Temp Sensor! 2008 ProStar... )**

That would it.

Chamberpains · 04-22-2018, **(Subject: I found the Ambient Air Temp Sensor! 2008 ProStar... )**

Wow they really don't change the design of something. That looks like the exact 1 they used in the late 90's Century class. They used to mount them in the air dam section of the bumper and road debris would annihilate them.

74bassman · 05-03-2018, **(Subject: I found the Ambient Air Temp Sensor! 2008 ProStar... )**

I found mine, right where Waterloo said. I disconnected the sensor to cleaned it up. Relocated to behind the front bumper ( I'm looking to make a pig tail to mount it up on the windshield cowl. I don't like to cut factory wires.) My AC will freeze me out now.

Daytripper · 06-10-2019, **(Subject: I found the Ambient Air Temp Sensor! 2008 ProStar... )**

2010 prostar daycab...should I have the outside display on my dashboard cluster? Nothing but odometer...I even clicked thru the rest of the functions and no ambient temp readings.

This may explain why my a/c is cold in the am but during the heat of the day blows lukewarm...been chasing this a/c problem for quite a while now(new thermistors, new high temp cut out sensor, 2 new actuators, new receiver dryer, new a/c compressor). There is supposed to be a third actuator on the engine side...not sure if I can access it without evacuating the system...
I am getting lukewarm air thru dash vents when blower fan is off, driving down the road.... oh and also after replacing the g#**@@* 1800.00 body controller (thanks international)

Waterloo · 06-10-2019, **(Subject: I found the Ambient Air Temp Sensor! 2008 ProStar... )**

(06-10-2019 )Daytripper Wrote: 2010 prostar daycab...should I have the outside display on my dashboard cluster? Nothing but odometer...I even clicked thru the rest of the functions and no ambient temp readings.

This may explain why my a/c is cold in the am but during the heat of the day blows lukewarm...been chasing this a/c problem for quite a while now(new thermistors, new high temp cut out sensor, 2 new actuators, new receiver dryer, new a/c compressor). There is supposed to be a third actuator on the engine side...not sure if I can access it without evacuating the system...
I am getting lukewarm air thru dash vents when blower fan is off, driving down the road.... oh and also after replacing the g#**@@* 1800.00 body controller (thanks international)

You need one of these, I think it will solve quite a few problems...https://amzn.to/2Iwx9jh

Here is the switch you will need to properly operate the valve... https://amzn.to/2KfZrlt

Install it in the heater core inlet line. I have one and love it! I have heat and cold air, no more opening the hood to turn that heater core valve!

Daytripper · 06-10-2019, **(Subject: I found the Ambient Air Temp Sensor! 2008 ProStar... )**

Well I replaced the ambient temp sensor....still no outside air temp displayed on my dash??? No change in A/C performance either....

Waterloo · 06-11-2019, **(Subject: I found the Ambient Air Temp Sensor! 2008 ProStar... )**

(06-10-2019 )Daytripper Wrote: Well I replaced the ambient temp sensor....still no outside air temp displayed on my dash??? No change in A/C performance either....

Check the wiring under the loom, it may have broken up line, that would be my first guess as to your problem.

If the wiring looks good, Google the Navistar Body Builder schematics on the internet. These trucks run on that CanBus system, it may be a sensor up or downline that is bad that the ambient temp sensor runs through. On my ProStar the ABS brakes and exhaust brake run through the compass. Yes, the compass. I had to replace that to get my engine brakes and ABS to operate. Can't make this sheet up.

And get that valve and switch I linked to above. I just installed both in my 2008 ProStar, nice having heat and AC when I want without having to get out of the truck and under the hood to turn that valve on and off. Best $35 I have ever spent.