FAIL-SAFE ELECTRONICS CONTROL DIESEL CARS.

An electronic diesel control system offers functional advantages over mechanical controls, although the latter are reliable and have low failure rates. Failure of exhaust gas recirculation is not critical, but failure of start of injection control can lead to engine damage. Countermeasures are also needed for fuel delivery control, where failure can create serious safety hazards. Potential defects in sensors, in the digital signal processor, and in the overall system described, can be detected. A variety of countermeasures are used, with a guideline of preventing engine damage and permitting emergency vehicle operation. If such measures cannot be implemented, the engine is shut off, the shut-off device being a redundant feature.