JLG boom lifts (450AJ, 600AJ, 800AJ, 460SJ, 660SJ, 860SJ, 1250AJP, M450AJ, M600JP)
JLG error code 9979 — FUNCTIONS LOCKED OUT - GROUND MODULE SOFTWARE VERSION IMPROPER
Message on the display: FUNCTIONS LOCKED OUT - GROUND MODULE SOFTWARE VERSION IMPROPER · flash code 9/9
Code 9979 occurs in machines: JLG 860SJ, 800S, 1250AJP, M600JP, E600JP, 1100S, 1100SJP, 340AJ, 400S, 460SJ, 600SC, 600SJC, 660SJC.
blocking fault
Temporary fault for the telematics project. The model needs to be a 600S or 1350S if not this fault will be generated and Platform controls will be prevented. This fault was to ensure that the software will only work for these two models.
Description from the JLG service manual, in the original wording.
Possible causes
The manual does not list the causes for this code: the service technician establishes them during diagnosis of the machine.
Checks from the manual
- Disable all machine and engine functions (i.e., command engine shutdown and do not permit start).
What service does
A qualified service technician reads the code with the manufacturer's diagnostic tools, finds the cause, clears the code and carries out a function test.
Source: JLG Service and Maintenance Manuals: 600AJ (3121201), 800AJ (3120858), 460SJ, 860SJ, 1250AJP (3122581800), M450AJ (3121829), M600JP (3121711), Diagnostic Trouble Codes tables.
The descriptions are quoted from the manufacturer's service documentation and are for guidance only. Clearing codes, calibrations and repairs are carried out by a qualified service technician according to the manual for the specific serial number. A machine with an active blocking code must not be used until the cause has been removed.
Does code 9979 not go away?
RK Rental services JLG lifts at our workshop or on site at the customer's premises (construction site, factory, warehouse). We read the code, remove the cause and select the parts by serial number.