TM 5-5420-234-14&P
4-12. UNIT TROUBLESHOOTING (continued).
7.
HOURMETER DOES NOT OPERATE (MODEL A ONLY) (continued).
4.
KNOWN INFO
TEST OPTIONS
No voltage at junction
Continuity Test.
Is there continuity mea-
box terminal strip.
sured on the (24-pin)
REASON FOR QUESTION
Cab control box OK.
linking harness between
cab control box connec-
The hourmeter power
POSSIBLE PROBLEMS
tor (P2) and main junc-
source is transferred
tion box connector (P4)?
Linking harness faulty.
from the cab control box
Junction box harness
to the main junction box
faulty.
via the (24-pin) linking
harness. Faults in this
harness will prevent
hourmeter operation.
Replace (24-pin)
linking harness
NO
YES
4-126
Change 1
