The I/O PCB is the interface between the control and the all of switches, motors, sensors, solenoids etc.

The I/O PCB is split into two parts, inputs [1] and outputs [2]. Most are independent from one another.

Corrective Action:

Check Voltages to I/O PCB

 Note: The plug numbers listed below apply to Classic Haas Control I/O PCB rev S or higher.  Measure the voltage on the backside of the corresponding connector on the I/O PCB. Use a volt meter equipped with needle tip probes.

• Check the 5 VDC and 12 VDC at P60 [1] from the Low Voltage Power Supply (LVPS).
• Check the 3-phase 120 VAC at P56 [2] these voltages drive the solenoids, oil pump, fans and other 120 VAC devices. If no voltage present. Check the CB6 circuit breaker on the Power Distribuition PCB.
• Check the 1-phase 120 VAC at P83 [5] this voltage drives the worklight and the high intensity lights. If no voltage present. Check the GFCI outlet on the side of the machine to make sure is not tripped. Also check the GFI/Worklight circuit breakers on the Power Distribuition PCB.
• Check the 3-phase 240 VAC at P44 [3] these voltages drive the coolant pump, TSC motor, hydraulic power unit on a lathe. If no voltage present. Check the Coolant and TSC circuit breakers on the Power Distribuition PCB.
• Check the 3-phase 240 VAC at P39 [4] these voltages drive the chip auguer or conveyor. If no voltage present. Check the Conveyor circuit breaker on the Power Distribuition PCB.
• If there is voltage present. Check cables and connections see section 2.

Corrective Action:

1. Release [EMERGENCY STOP].
2. Press [RESET]. This clears the alarm and applies power to the servo motors.
3. Use a multimeter with needle-tip test probes to measure the voltage across pins 1 and 2 on the P79 or P78 connector on the I/O PCB. The voltage should be between 18 and 30 VDC.

 Note: Do not measure the voltage with the axis brake cable disconnected from the P79 or P78 connector on the I/O PCB.

Corrective Action:

• Make sure the power cable or cables for the system from Section 1 are seated properly and are secure in place.
• Make sure the connector pins are seated properly and are secure in the housing.
• Clean contaminated connectors. Re-seat the connectors and make sure they are secure.
• Perform a visual inspection on the cables. Look for signs of damage or puncture. Replace cables if there is visible damage.
• Check the cable connections between P64, P65, P70, and P61 [2] on the I/O PCB and P11, P12, P13, P14 [1] on the Mocon/Maincon. These cables are the same and can be interchanged with each other for testing.
• For some systems the power to the worklight is protected by a GFCI outlet on the side of the machine, make sure the GFCI is not tripped and that is functioning properly.

Corrective Action:

• Verify on the DIAGNOSTICS screen that the output was commanded.
• Look for burned contacts in the relays. Replace the K9 - K12 relays as needed. (Only for Tool changer, APC motor, Servo Bar 300 carriage motor issues only)
• Look for burnt components or traces on the I/O PCB.
• Perform all tests measurements and inspections listed in sections 1 to 3.
• If all voltages are OK, cables are OK and have no signs of visual damage, motors have checked OK, sensors have tested OK, and the problem still reoccurs, then the I/O PCB may have failed.
• Replace the I/O PCB.