Pinpoint Test N : The Air Conditioning (A/C) Is Always On - A/C Mode Always Commanded On: Notes

WARNING: This page is about a different car, the 2015 Lincoln MKT. However, it is still accessible from the selected car via links, so may be relevant.

Diagnostic Overview

Diagnostics in this article assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to Diagnostic Methods in Service Information for information about these practices.

Refer to Automatic Climate Control System , for schematic and connector information.

Normal Operation and Fault Conditions

When the A/C is requested, the FCIM sends the button press message over the I-CAN to the IPC. The IPC then sends the button press message to the BCM over the HS-CAN. The BCM sends the button press message to the HVAC module over the MS-CAN. The HVAC module sends an A/C request message through the MS-CAN to the BCM and the BCM sends the A/C request through the HS-CAN to the PCM.

DTC Fault Trigger Conditions

DTC	Description	Fault Trigger Conditions
P1464	A/C Demand Out Of Self Test Range: No Sub Type Information	This DTC sets when the PCM senses an A/C request during a PCM self-test.

Possible Sources

Wiring, terminals or connectors
FCIM
PCM
HVAC module

Visual Inspection and Diagnostic Pre-checks

Inspect loose or corroded PCM or HVAC module connections.