62-11389
7
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55
Alarm
NO.
Steps
Alarm/Cause
Corrective Action
86
CHECK UL2 CIRCUIT
•
TRIGGER–ON: Rear Unloader (UL2) circuit is shorted. (The UL2 output from the microprocessor
(3MP23) is negative, so the circuit will not be shorted to ground, but is shorted either within UL2
itself, or to a positive wire.)
•
UNIT CONTROL: Engine and Standby Operation: alarm only.
•
RESET CONDITION: Auto Reset when the UL2 Coil current (amp) draw is normal, or alarm may
be manually reset via keypad or by turning the unit off, then back on again.
NOTE: Follow the steps below until a problem is found. Once a repair or correction has been made, the active
alarm should clear itself (see reset condition above). Operate the unit through the appropriate modes to see if
any active alarm occurs. Continue with the steps below as necessary.
1
Check Rear Unloader (UL2) Coil
a. Inspect Rear Unloader (UL2) coil &
connector.
No damage to coil.
No damage, moisture, or corrosion in connector.
b. Check resistance of coil.
Refer to Section 2.12 for correct electrical values.
Cannot be opened (infinite ohms), shorted (Zero
Ohms) or shorted to ground.
c. Check amp draw of coil.
Refer to Section 2.12. Use ammeter.
2
Check Rear Unloader (UL2) Current Draw
Use Component Test Mode to test
actual current draw of the circuit.
(Refer to Section 5.2.2.)
Refer to Section 2.12 for correct electrical values.
View current draw in Data List.
3
Check Rear Unloader (UL2) Coil Wiring
Inspect harness & control box con-
nector pins & terminals. (See wiring
schematic Section 10.)
No physical damage to harness.
No damage, moisture, or corrosion in connectors.
