Lull 6K Service Manual User Manual
Page 554
Transmission
8-6
Service Manual — Models 644B, 6K, 844C, 8K, 1044C, 10K
9. Check transmission pressure. Control pressure should be 230–260 psi
(16–18 bar). See “ZF Transmission Pressure Checks” on page 8-23.
Testing ZF Transmission Electrical System
ZF Transmission with DW-2 Shifter
644B-37 (S/N 101–880)
6K-37 (S/N 101–397)
6K-42 (S/N 101–131)
644B-42 (S/N 101–241)
844C-42 (S/N 101–783)
8K-42 (S/N 101–261)
1044C-42 (S/N
101–121)
10K-42 (S/N 101–107)
1044C-54 (S/N 101–25)
10K-54 (S/N 101–107,
109)
If an electrical supply problem is suspected, the operator may also
experience circuit failures, alternator/charging problems, or starting
problems. These problems should be addressed and corrected prior to
proceeding with diagnosis of the ZF transmission electrical system. Once
this is done, proceed with the following steps:
1. Check battery integrity to ensure that it has not discharged.
2. Check battery cable connections.
3. Check 30 amp circuit breaker to ensure that it is not defective or stuck
in open position.
4. Check battery post connection at ignition switch.
5. Check the ignition switch as follows:
a. With the ignition switch in the “OFF” position, only the Bat. Post
should be active.
b. With the ignition switch in the “ACC” position, only the Bat. Post
and the Acc Post should be active.
c. With the ignition switch in the “ON” position, only the Bat. Post, Acc
Post, and the Ign Post should be active.
d. With the ignition switch in the “ST.” position, only the Bat. Post, Ign
Post, and St. Post should be active.
6. Check ignition switch relay (if equipped).
7. Check 7.5 amp fuse (8 amp fuse for early production models) and fuse
holder.
8. Check shifter signals. See “DW-2 Speed Range/Direction Signal Test”
on page 8-7.
9. Check shifter signals at the transmission solenoid assembly. See
“DW-2 Signals from EST-19 to Transmission Solenoid Assembly Test”
on page 8-8.
10. Check park brake switch, service brake pressure switch, and proximity
switch. See pages 8-17, 8-18, and 8-20.