1739

Common Causes

• Low hydraulic oil level in the power unit
• Defective hydraulic pump/motor
• Loss of air supply pressure (air chuck machines)
• Faulty pressure confirmation switch or wiring on the chuck circuit

Troubleshooting Steps

1. 1Read the code number shown with the alarm: code 100 = Front chuck low clamping pressure continued for 2 s (I/O NO.24 bit 4 iCPA/, or NO.38 bit B iAPA/ for air chuck); code 101 = Rear chuck low clamping pressure continued for 2 s; code 102 = Tailstock chuck low clamping pressure continued for 2 s (I/O NO.56 bit 3 iTSCPA/); code 103 = Face driver low moving pressure continued for 2 s; code 104 = Front air chuck pressure dropped during spindle rotation; code 105 = Rear air chuck pressure dropped during spindle rotation
2. 2Read the code: 100 = front chuck low pressure, 101 = rear chuck, 102 = tailstock chuck, 103 = face driver, 104/105 = front/rear air chuck pressure dropped during spindle rotation.
3. 3Check the hydraulic unit oil level first and top up if low; then verify the hydraulic pump motor runs and builds pressure.
4. 4For air chuck codes, verify shop air supply pressure to the machine and the air chuck regulator setting.
5. 5Confirm the pressure switch input in the I/O check screen: code 100 uses NO.24 bit 4 (iCPA/) or NO.38 bit B (iAPA/) for air chuck; code 101 uses NO.32 bit 5 (i2CPA/) or NO.38 bit F; code 102 uses NO.56 bit 3 (iTSCPA/). A 0 reading with normal pressure points to the switch or its wiring.
6. 6Do not run the spindle with low chuck pressure; if pressure and inputs check out but the alarm returns, record the alarm number and code and contact Okuma service.