Engine Controls - Tests W/Codes - Pcm/BCM: Description
Self-diagnostic system uses several electronic components which can be controlled by service technician to provide valuable self-diagnostic information. Components are part of an electrical network designed to control various engine and body subsystems.
At the heart of the computer system is the Body Control Module (BCM). The BCM is located behind the glove box. All sensors and switches are monitored by the BCM or by one of the following major components:
- Cathode Ray Tube (CRT) Control Module (optional equipment)
- Electronic Control Module (ECM)
- Electronic Climate (Heater and A/C) Control Panel (ECCP)
- Instrument Panel Cluster (IPC)
- Heating and A/C (HVAC) Programmer
- SIR Diagnostic Energy Reserve Module (DERM) controller
The Cathode Ray Tube (CRT) is a touch sensitive color "monitor" located in climate control/radio center for setting temperature controls and accessing BCM diagnostic features. NON-CRT equipped units have an Electronic Climate Control Panel (ECCP) with LED digital display area for temperature and override mode values. Both CRT and ECCP are used to access BCM diagnostics and display them in IPC information center's 20 character LED display bar.