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Charger Tech Training Body Electrical: Modules and Modules
Ed. note: Charger Technician Training, in a wide variety of two-day training blocks, is available at dozens of Chrysler training locations across the United States. There is no prerequisite for the training, and it is open to all fleet personnel from the fleet manager to the maintenance and repair technician. This is the same factory training given to dealership technicians. This same police- specific training will also be available in-house at the police and sheriffs’ departments running larger fleets of Chargers.
For more information on Charger Technician Training, contact Fleet Service Manager George Bomanski, Chrysler Group, at (407) 257-1532 or via firstname.lastname@example.org. This training is scheduled about six months in advance. Because the training is definitely hands-on, the class size is limited to 12 techs. The host department needs to provide one 2006-2007 Charger and one 2008-2010 Charger per class, as the electrical architecture of each generation of Charger is so different.
The police Charger is loaded with modules and controllers. Modules are everywhere. Today’s tech needs to know the features and locations on more than a dozen interior, exterior and trunk modules when working on the police Charger.
The Charger Tech Training Body Electrical course identifies all the modules, modes, drivers and sensors in the Charger. This includes what functions they control, what features they have and where they are located. The course especially focuses on police-specific modules.
The review of the Charger’s modules also includes the front power distribution center on the right fender well and the rear power distribution center in the trunk. The full and detailed schematic for each is reviewed. However, learning all the new acronyms is first. And the manual for the course has three pages of acronyms.
NGC stands for Next Generation Controller (the powertrain control module), CCN is the Cabin Compartment Node (the body control module), and FCM is the Front Control Module (a combination power distribution center and CAN bus gateway).
Powertrain Control Module
The powertrain control module (NGC) is located against the firewall on the right side near the hood hinge and under windshield mesh panels. Why was such an important module put in such a difficult to access location?
One reason is to make you think twice, or even three times, before removing and replacing it! The NGC is almost never at fault and almost never needs to be replaced. Yet is it one of the most frequently misdiagnosed part replacements. The problem is almost always elsewhere.
The Central Gateway Module (CGW) is incorporated into the Front Control Module (FCM). The CGW is where both CAN C bus and CAN B bus connect together. The CGW is similar to a router in a computer network and allows data exchange between CAN C and CAN B. The CGW is also the gateway to the CAN network for the scan tool using its own CAN bus circuit, which is called the Diagnostic CAN C. This diagnostics circuit operates in real time, i.e., 500 KB per second.
Body Control Module
The Cabin Compartment Node (CCN) combines the functions of a Mechanical Instrument Cluster (MIC) with a Body Control Module (BCM). The CCN receives sensed, switched and bussed inputs. It also controls power distribution by using high side drivers, low side drivers, relay drivers and push-pull drivers. The CCN can send high speed interior CAN B bus messages to other modules.
Most exterior lights are controlled by the FCM based on bus messages from the CCN and the Steering Control Module (SCM). The exceptions are the brake lights and the Center High Mounted Stop Light (CHMSL), which are hardwired to the brake pedal switch.
The CCN uses 5-volt reference signals (different amounts of voltage) to determine OFF, Park Lamp, Headlamp, Autolamp and Fog Lamp selections. The CCN sends the FCM this information over the CAN B bus. The CCN also provides diagnostics for the headlamp circuit. This includes high beam, low beam and flash-to-pass.
Power Distribution Centers
The police Charger has two power distribution centers (PDC) where the majority of the electrical system fuses and relays are housed. The front PDC is under the hood on the right side of the engine compartment. The rear PDC is located in the trunk, near the battery, under the hinged trunk floor trim.
The front PDC is combined with the FCM and the CGW. This combined unit is called the Integrated Power Module (IPM). This is where direct control over the PDC relays and circuits occurs. Importantly, this also serves as the central gateway for the CAN bus system.
You cannot just swap modules from wrecked cars or use them as replacement parts. Most module swaps will throw a DTC that references as a mismatched VIN. Many modules keep track of the “original” VIN, which cannot be changed, and the “current” VIN, which can be changed by a scan tool.
The CCN, i.e., the body control module, is even more unique. When this is replaced, you must request to have the vehicle’s odometer mileage burned into the CCN before it is shipped.
Pop quiz: Where is the high side driver that supplies power to the reverse lamps? Front Control Module. How about the relay driver for the radiator fan relays? Front Control Module. How about the relay for the fuel pump? It is located in the Front Control Module, but controlled by the NGC (powertrain control module).
Published in Police Fleet Manager, Jul/Aug 2010
Rating : 10.0
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