Glow Plug System; Glow Plug System Overview; Glow Period; Extended Glow Period - Volkswagen 1.9-Liter TDI Owner's Manual

Glow Plug System

The glow plug system makes it easier
to start the engine at low outside
temperatures. It is activated by the
Diesel Direct Fuel Injection Engine Control
Module J248 at coolant temperatures
below 48°F (9°C).
The Glow Plug Relay J52 is activated by the
Diesel Direct Fuel Injection Engine Control
Module J248. The Glow Plug Relay J52
then switches on the working current for
the Glow Plugs Q6.
Function
The glow process is divided into two
phases, the glow period and the extended

glow period.

Glow Plug System Overview

Engine Speed
Sensor G28
Engine Coolant
Temperature
Sensor G62
Glow Plug System
Glow Period
The glow plugs are activated when the
ignition is switched on and outside
temperature is below 48°F (9°C). The Glow
Plug Indicator Light K29 will light up.
Once the glow plug period has elapsed, the
Glow Plug Indicator Light K29 will go out
and the engine can be started.

Extended Glow Period

The extended glow period takes place
whenever the engine is started, regardless
of whether or not it is preceded by a glow
period.
This reduces combustion noise, improves
idling quality and reduces hydrocarbon
emission.
The extended glow phase lasts no more
than four minutes and is interrupted when
the engine speed rises above 2500 rpm.
Diesel Direct Fuel Injection
Engine Control Module J248
Glow Plug
Relay J52
Glow Plugs Q6
Glow Plug
Indicator
Light K29
SSP209/099
53