CONTROL GP-ELECTRONIC 3808262 - Caterpillar

Table 1
C-12 Truck Engine Specifications    
Cylinders and Arrangement     In-line 6 cylinder    
Bore    
130.0 mm (5.12 inch)    
Stroke    
150.0 mm (5.91 inch)    
Displacement    
12 L (732 in 3 )    
Firing Order     1-5-3-6-2-4    
Rotation (flywheel end)     Counterclockwise    
Jake Brake brake slave piston lash    
1.14 0.08 mm (0.045 0.003 inch)    The C-12 truck engine has the following characteristics: direct fuel injection, electronic unit injection that is mechanically actuated, turbocharged and air-to-air aftercooled (ATAAC).The electronic engine control system provides the following functions: electronic governing, automatic air to fuel ratio control, torque rise shaping, injection timing control and system diagnostics.Several programmable features are included in the electronic control: cruise control, governing the PTO, vehicle speed limiting, rpm limit for high gears, rpm limit for low gears, top engine limit, idle shutdown timer and control for the engine retarder (compression brake).Additional benefits provide engine fuel economy, serviceability, and operator comfort. The additional benefits include the following features: improved cold starting capability, resistance to tampering, diagnostics, progressive shift engine speed control, data link (SAE J1587) for the American Trucking Association (ATA) and optional Engine Monitoring Package.An electronic governor controls the output of the unit injectors in order to maintain the engine rpm that is desired. The functions of the governor include a programmable low idle and a 20 rpm to 200 rpm governor overrun.Very high injection pressures are produced by electronically controlled, mechanically actuated unit injectors. The injectors combine the pumping and the electronic fuel metering (duration and timing) during injection. The unit injectors accurately control smoke limiting, white smoke, and engine acceleration rates.There is one unit injector per cylinder. Individual unit injectors meter the fuel. The individual unit injectors also pump the fuel. The metering and the pumping is done under high pressure. High injection pressures help to reduce fuel consumption and emissions. The use of this type of unit injector provides total electronic control of injection timing. The injection timing varies with engine operating conditions. The engine performance is optimized in the following areas:
starting
emissions
noise
fuel consumption
driveabilityThe timing advance is achieved through precise control of the injector firing. Engine speed is controlled by adjusting the firing duration. The information is provided to the Electronic Control Module (ECM) by a speed timing sensor. The information is for detection of cylinder position and engine speed.The engines have built-in diagnostics in order to ensure that all of the components are functioning and operating properly. In the event of a system component deviation from the programmed limits, the operator will be alerted to the condition by a CHECK ENGINE/DIAGNOSTIC lamp that is mounted on the dashboard. An electronic service tool that is provided by Caterpillar or the cruise control switches (if equipped) may be used to read the numerical code of the diagnostic flash code. There are three types of diagnostic codes: ACTIVE, LOGGED and EVENT. These codes are logged and stored in the ECM. Refer to the Operation and Maintenance Manual,