gf2010d3000hd

Component description for coolant pump switchover valve

Type gf · topic 20.10 · version 0100 · 2011-07-21

Applies to: ENGINES 651.940 in MODEL 639.6 /70 with CODE (XZ1) Model generation 1 with CODE (MZ0) BlueEFFICIENCY

Where it sits

Function group 1 Engine › 20 Engine cooling system › 20.10 Coolant pump, coolant thermostat — Series 639 (models 6**, 70*) · Series 651 (models 940)

GF20.10-D-3000HD

Component description for coolant pump switchover valve

22.6.11

ENGINES 651.940 in MODEL 639.6 /70
with CODE (XZ1) Model generation 1
with CODE (MZ0) BlueEFFICIENCY

Component description for coolant pump switchover valve

S20.10-4524-06

View of engine from left

M16/45 Throttle valve positioner

Y19/10 Coolant pump switchover valve

Location

The coolant pump switchover valve is located at the front on the engine on the left on the throttle flap positioner.

Task

The coolant pump switchover valve controls the coolant feed to the coolant pump.

Component description for coolant pump switchover valve

S20.10-4525-01

Design

1 Ventilation connection (atmospheric)

2 Vacuum pressure supply connection

3 Connection for the coolant pump vacuum unit

Y19/10 Coolant pump switchover valve

In a de-energized condition the coolant pump switchover valve is open.

The coolant pump is activated in the post-start phase if one of the following conditions is met:

- The max. shutoff time (depending on the model and engine power) of 500 s after engine start is reached

- Engine speed or injection quantity exceeds the defined limit value

- The post-start phase limit values for intake air temperature and coolant temperature and for the total injected fuel quantity stored in the control unit performance map are reached

- The request "Heat" was received from the rear AA/C rear A/C control unit (N19/3)