DAF LF45, LF55 Series. Manual - part 236

©

 200508

2-5

Description of components

PNEUMATIC GEARBOX CONTROL

ΛΦ45/55 series

3

3

2.4 NEUTRAL POSITION VALVE

The neutral position valve is mounted on the 

selector shaft housing. Inside the selector shaft is 

a slot that corresponds to the neutral position of 

the selector shaft. The neutral position valve pawl 

drops into this slot. When a gear is engaged, the 

neutral position valve pawl moves out of the slot, 

thereby switching the valve. In the neutral 

position the system pressure is sent to the 

electropneumatic downshift protection valve. In 

the event of a gear change, the gear lever and the 

neutral position valve will be moved through the 

neutral position. At that moment the neutral 

position valve sends the system pressure from 

connection (21) to the electropneumatic 

downshift protection valve.

V3 00 476

PNEUMATIC GEARBOX CONTROL

2-6

©

 200508

Description of components

3

ΛΦ45/55 series

3

2.5 RANGE GROUP ENGAGING CYLINDER

The range group engaging cylinder is mounted 

on the rear of the gearbox.

The engaging cylinder is supplied from the 

electropneumatic downshift protection valve.

V3 00 479

L

H

©

 200508

3-1

Inspection and adjustment

PNEUMATIC GEARBOX CONTROL

ΛΦ45/55 series

3

3

3. INSPECTION AND ADJUSTMENT

3.1 PROGRAMMING PARAMETERS USING DAVIE

After a gearbox has been replaced by a gearbox 

that uses a different reduction rate, it will be 

necessary to reprogram the VIC by means of 

DAVIE XD.

This is to ensure that the downshift protection 

valve is enabled and disabled at the correct 

vehicle speeds.

It is not possible to adjust the frequencies of the 

gate protection and the range-change protection 

with the standard program of DAVIE XD. If the 

vehicle configuration is changed, this should 

always be reported.

PNEUMATIC GEARBOX CONTROL

3-2

©

 200508

Inspection and adjustment

3

ΛΦ45/55 series

3

3.2 SIMULATING SPEED SIGNAL

The speed signal can be simulated with DELSI 

(DAF no. 0694941). DELSI must be connected to 

the speed sensor connector.

Before connecting DELSI to the speed sensor 

connector, an adapter cable must be made.

The adapter cable must consist of the following 

wiring:

When the speed sensor connector is 

disconnected, a fault is stored in the tachograph. 

This fault can be deleted using DAVIE XD.

V300425

2

4

3

1

K100873

Pin 1: speed sensor, power supply
Pin 2: speed sensor, earth
Pin 3: speed sensor, "real-time" 

speed/distance signal

Pin 4: not in use