Heater, Air Intake: Operation: Operation

WARNING: This page is about a different car, the 2015 RAM 3500 HD and 2015 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

The air heater element is used to heat incoming air to the intake manifold. This is done to help engine starting and improve driveability with cool or cold outside temperatures.

Electrical supply for the air heater element is controlled by the Powertrain Control Module (PCM) through the air heater relay. Refer to RELAY, INTAKE AIR HEATER for more information.

A heavy-duty cable connects the air heater element to the air heater relay. This cable will supply 12-volts to an individual heating element within the heater block assembly.

The following chart displays the pre-heat, or turn-on times (in seconds) of the wait-to-start lamp. If the intake manifold temperature is above 66.09 degrees Fahrenheit, the wait-to-start lamp will not illuminate. Consequently, the intake air heater element will not be activated.

WAIT-TO-START LAMP TURN-ON TIMES

PRE-HEAT TIME WITH INTAKE MANIFOLD TEMPERATURE AT: (IN DEGREES ° F)	PRE-HEAT TIME WITH BARO AT: (IN. HG.)
	19.99 IN. HG	23.00 IN. HG.	25.00 IN. HG.	26.99 IN. HG.	29.00 IN. HG.
-40.00° F	75.0 seconds	75.0 seconds	30.0 seconds	30.0 seconds	30.0 seconds
-29.00° F	75.0 seconds	75.0 seconds	30.0 seconds	30.0 seconds	30.0 seconds
-17.80° F	75.0 seconds	75.0 seconds	30.0 seconds	30.0 seconds	30.0 seconds
-17.79° F	15.0 seconds	15.0 seconds	15.0 seconds	15.0 seconds	15.0 seconds
-9.43° F	15.0 seconds	15.0 seconds	15.0 seconds	15.0 seconds	15.0 seconds
-9.38° F	10.0 seconds	10.0 seconds	10.0 seconds	10.0 seconds	10.0 seconds
0.00° F	10.0 seconds	10.0 seconds	10.0 seconds	10.0 seconds	10.0 seconds
10.00° F	10.0 seconds	10.0 seconds	10.0 seconds	10.0 seconds	10.0 seconds
18.89° F	10.0 seconds	10.0 seconds	10.0 seconds	10.0 seconds	10.0 seconds
19.00° F	00.0 seconds	00.0 seconds	00.0 seconds	00.0 seconds	00.0 seconds