P15.20-A002-79
Example illustration of engine 656 |
1 | Glow output stage |
Overview
This document contains information on:
General
Function requirements
Function
General
The glow output stage initiates the glowing process.
The glow plugs are screwed into the cylinder head below the rail. The glow plugs heat up the combustion chamber and support burning as well as the soot particulate filter regeneration to minimize pollutants. Ceramic glow plugs are installed. Ceramic glow plugs reach a glow temperature which is approx. 200 °C higher than conventional glow plugs. The constant temperature of the glow plugs is around 1250 °C, which enables exceptional starting characteristics even at low temperatures.
The properties of ceramic glow plugs are:
Reduced energy consumption
Optimum starting characteristics
Rapid temperature increase
High conductivity
High glow temperature
Long service life
Function requirements
Engine management ON (circuit 87M)
Engine oil temperature < 40 °C
Function
The combustion engine control unit transmits control signals which the glow output stage turns into a characteristics map-dependent glow plug voltage.
The glow function is interrupted if no data transfer takes place with the combustion engine control unit.
The glow output stage constantly reports its current operating condition (preheat "ON" or "OFF") to the combustion engine control unit.
System errors are transmitted to the combustion engine control unit.