32 - 5
Powershift Gearbox - 4 Speed (cont’d)
Electrical Connections - Quick Reference (cont’d)
The tables show switch positions together with energised
relay and gearbox solenoids for each gearbox function. The
numbers show which contacts are ‘live’ and also relate to
the actual connector pin numbers.
When fault finding it should be remembered that the system
relies on the dump switch and park brake switches
functioning correctly, failure of these switches will prevent
both forward and reverse being selected. From the tables it
is possible to see common relay functions which can help
trace faults. For example we can see that relay FF2 is
energised to engage 1st or 2nd gear. Failure of these gears
to select may indicate a fault with relay FF2.
Note that a non functioning relay or solenoid may not
indicate a faulty component, the associated wires and
connectors may have failed. For wire and connector details
see the relevant schematic.
Diagram Y
The diagram
Y
opposite shows the electrical circuit for the
gearbox control. It is shown with 3rd gear reverse selected.
‘Live feed’ wires are coloured red and feed to earth are
green.
Key
C50
Reverse alarm
DW
Park brake switch
FL
Column switch connector
FK
Diode gate connector
FG
Transmission dump relay
FD2
Forward relay
FE2
Reverse relay
FF1
Interlock relay
FD1
Forward Hi/Lo relay
FE1
Reverse Hi/Lo relay
FF2
Mainshaft/Layshaft relay
NG
Dump switch
Gearbox Solenoids
V
Reverse high
W
Reverse low
Y
Mainshaft
Z
Layshaft
Note:
Solenoid
S
is the
2/4WD solenoid. The 2/4WD
select electrical system is
not described in this
section.
Section F
9803/3280
Section F
32 - 5
Issue 1
Electrical Connections
A404820
FD2
FD1
FE2
FE1
FF2 FG
FF1
F
N
R
1
2
3
4
DW
3
2
3
2
1
3
2
1
6
8
7
91
0
2
5
1
43
3
2
1
14 13 12
7
6
5
4
11 10
9
8
1
4
3
5
6
7
11
2
NG
FK
FL
A
B
A
B
A
B
12
4
14
7
10
1
2
3
4
F
N
R
9
13
1
2
3
12 13 14
4
5
6
7
8
9
10 11
S
A405330
