Air Control Valve (Acv) Description; Emissions Control Module (Ecm) Description; Figure 3.6 Air Control Valve (Acv); Figure 3.7 Emissions Control Module (Ecm) - Carrier UG 15 Tier 4 Operation And Service Manual

3.4

Air Control Valve (ACV) Description

The Air Control Valve (ACV),
open valve that is located on the engine air intake hose. When the DPF requires regeneration and exhaust
temperature is very low (for example, during minimal engine loading and/or extremely cold weather), the ACV is
used for active-assist regeneration. During active-assist regeneration, the ACV changes the air-to-fuel ratio in
order to raise exhaust temperatures high enough for the doser to activate and regenerate the DPF. Refer to
Section 3.7 for a description of how regeneration works.
3.5

Emissions Control Module (ECM) Description

The Emissions Control Module (ECM),
sensor, along with temperature sensors mounted in three locations of the exhaust system. Based on the
parameters, the ECM will initiate automatic regeneration when needed. Further diagnosing with the ECM requires
the ECM Service Tool software. Refer to
The ECM will signal to the service light,
light indicates immediate service is needed, and will continue to operate for up to 250 hours in order to protect load
and allow adequate time for delivery. After 250 hours, the unit will shut down until the EES is repaired.
T-378
Figure 3.6, restricts engine intake air to raise exhaust temperatures. It is a normally-

Figure 3.6 Air Control Valve (ACV)

Figure 3.7, monitors the EES parameters, using an internal back pressure
ECM Service Tool

Figure 3.7 Emissions Control Module (ECM)

Figure 3.8, as part of alarm notification. A unit with an illuminated service

Figure 3.8 Service Light

chapter for procedures.
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