OPERATOR'S MANUAL MAINTENANCE

Section C - Electrics
Basic System Operation
Engine Pre Heat (Glow plugs)
C-32 C-32
9803/9880-3
Engine Pre Heat (Glow plugs)
Operation
C049890-2
Fig 35.
This feature allows the engine cylinders to be pre-heated,
before engine cranking to assist cold start performance.
When the key switch is turned to the `Ignition' position the
ECM detects the temperature to determine whether and
for how long preheat is required. The ignition provides a
positive feed to the Preheat relay and an input to the ECM
at i/p V24.
When preheat is required, the ECM gives a ground to the
heat relay coil from o/p V10. The relay energises, which
then allows battery voltage to cross the heat relay to the
glow plugs.
The ECM sends a `glow signal' message via the CAN bus
to the EMS which displays the message "PREHEAT".
When the key switch is turned to the `crank' position the
ECU1 sends a message via the CAN bus to the ECM to
start the engine.