Mitsubishi FB13PNT, Quick Start Manual

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2-107 2-107
501154 501154
CHAPTER 2 TROUBLESHOOTING FOR CONTROL CIRCUITS CHAPTER 2 TROUBLESHOOTING FOR CONTROL CIRCUITS
3.4 3.47 7 Hyd Hydrau raulic lic Loc Lock So k Solen lenoid oid Fau Fault lt (74 (74))
Error code: 74 Error code: 74
Situation Situation
Display: "74". Display: "74". Pump motor operatio Pump motor operation inhibited. Normal traction motor operatio n inhibited. Normal traction motor operation and power steering n and power steering
operation. operation.
Possible Possible
cause
cause
Faulty lift lock valve, faulty main harness, faulty logic unit. Faulty lift lock valve, faulty main harness, faulty logic unit.
Trigger of Trigger of
the error the error
code
code
By short circuit detection signal of By short circuit detection signal of logic card. logic card.
Checks Checks
(1) Disconnect battery plug, then perform inverter discharging work (1) Disconnect battery plug, then perform inverter discharging work
(2) D (2) D isconnect connec isconnect connec tor E-04 of logic tor E-04 of logic unit unit
(3) Chec (3) Chec k short circu k short circu it it between between E-1 E-1 3-1 3-1 and E-13-2 of harness sid and E-13-2 of harness sid e e
Shorted Shorted Not shorted Not shorted
(5) C (5) C heck s heck s hort circ hort circ uit between uit between E-13-1 and E E-13-1 and E -13- -13- 2 2 lift lift lock lock
valve side connectors valve side connectors
Measure coil resistance Measure coil resistance
[7.9 Ω at - [7.9 Ω at - 30 °C 30 °C (-22 °F) (-22 °F) to to 11.8 11.8 Ω at 80 °C ( Ω at 80 °C ( 176 °F 176 °F )] )] (MC) (MC)
[22.1 Ω at -30 °C [22.1 Ω at -30 °C (-22 °F) to (-22 °F) to 37.6 Ω at 80 °C ( 37.6 Ω at 80 °C ( 176 °F 176 °F )] )] (FC) (FC)
Normal Abnormal Normal Abnormal
(4) Repair or replace main harness (4) Repair or replace main harness
(6) Replace logic card of (6) Replace logic card of
log log ic ic un un it it
(7) R (7) R eplace lift lock eplace lift lock valve valve
Disconnect connector E-13 of lift lock valve Disconnect connector E-13 of lift lock valve