JLG boom lifts (450AJ, 600AJ, 800AJ, 460SJ, 660SJ, 860SJ, 1250AJP, M450AJ, M600JP)
JLG error code 438 — HIGH ENGINE TEMP
Message on the display: HIGH ENGINE TEMP · flash code 4/3
Code 438 occurs in machines: JLG 860SJ, 800S, 600AJ, 600S, 660SJ, 800AJ, 800A, 460SJ, 400S, 1250AJP, 1100S, 1100SJP, 340AJ, 600SC, 600SJC, 660SJC, 450AJ SII, 510AJ.
warning / function limited
(Ford engine only) The engine temperature is > 117 C. (Deutz engine only) The engine temperature is > 130 C.
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
- Ford / Deutz engine only.
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 438 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.