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Diesel CEC Tests W/Codes: Description

The Diesel Electronic Control (DEC) system is used on California 6.2L diesel engines with light duty emissions. The DEC system monitors various engine functions to electronically control the exhaust gas recirculation (EGR) system and torque converter clutch (TCC). The Electronic Control Module (ECM) is the "brain" of the system.

Fig 1: Engine Speed Sensor Location (Pickup Models Only)
G10271
Fig 2: MAP Sensor Location
G9477
Fig 3: Throttle Position Sensor Location
G9478
Fig 4: EGR System Components and Locations
G9479
Fig 5: Diesel Diagnostic Check Tester This tester must be used to determine system failures.
G9480
Fig 6: ALCL Connector Identification. ALCL is located under left side of dash on pickup models and under driver's seat on van models.
G9481
Fig 7: ECM Location. ECM is located under right side of dash on pickup models and under driver's seat on van models.
G9482
Fig 8: DEC System Component Locations for Trucks and Vans
G10279