Mack Granite Fault code 1-4

[jl464]

I have a 2006 Mack Granite with 400hp. Recently the lightning bolt came up on the dash and the code that comes up is 1-4 which is the ambient air temperature sensor but the truck is not equipped with the sensor. Ever since the bolt has come up the truck is cutting power on freeway when going uphill.What do you guys think is wrong?

[rsb502]

Hmm thats a thinker I was under the impression all aset engines had that sensor, let me do some research in my books here. I would guess if its not the sensor then there is an issue with the wiring harness going to the sensor location, I believe the engine harness has the plug there for the sensor and that if its not there and you are getting a code then the harness has been melted or pinched somehwere between the ECM and the Ambient air temp sensor plug, or there is water or something equally bad for electrical systems in the end of the plug.

[rsb502]

one quick way to check for the wiring issue is to locate the plug end and use a multi meter and check across the contacts if there is continuity between them something is up in the harness. I just thought about that sensor I dont think I have ever messed with one how many wires go to the sensor 1,2or 3 if its one check for a grounded wire using the engine ground on one lead two or three check across the wires, if its melted and grounding on the engine you can check like for one wire on all wires and you will know if one is grounded to the block.

[turckster]

I have a 2006 Mack Granite with 400hp. Recently the lightning bolt came up on the dash and the code that comes up is 1-4 which is the ambient air temperature sensor but the truck is not equipped with the sensor. Ever since the bolt has come up the truck is cutting power on freeway when going uphill.What do you guys think is wrong?

From the EIS (Electronic Information Systems) page for a 1-4 code with AI engine:

Failure Mode Identifier (FMI): 3 (Voltage High), 4 (Voltage Low), 5 (Current Low/Open)

Parameter Identification (PID): P171

Message Identification (MID): 128

Circuit Description: The Ambient Air Temperature (AAT) Sensor is a thermistor. The resistance of the AAT Sensor changes inversely to the temperature of the surrounding air. When the outside air temperature is cold, the sensor resistance is high. As the temperature of the air increases, the sensor resistance decreases. The Engine Electronic Control Unit (EECU) monitors the voltage drop across the AAT Sensor and uses the signal, along with other sensor signals, to calculate the fuel injection quantity and timing.

Location: The Ambient Air Temperature (AAT) Sensor is located near the front of the chassis. The AAT Sensor may be mounted on the front crossmember, hood hinge, body panel, spring bracket, grill guard, or behind the front bumper, depending upon chassis model.

Code Setting Conditions: The Electronic Malfunction Lamp (EML) will turn on and code 1-4 will set when the Engine Electronic Control Unit (EECU) senses an AAT Sensor signal less than 0.15 volts or greater than 4.4 volts for 1 second. If the AAT Sensor voltage returns to between 0.15 volts and 4.4 volts for more than 1 second, the fault will become inactive.

Normal AAT Sensor Parameters: The Ambient Air Temperature (AAT) Sensor has a resistance of 3482 ohms at 32°F (0°C) and 1485 ohms at 104°F (40°C).