TERUMO INFUSION PUMP - TROUBLESHOOTING - MEDICAL ELECTRONICS

I hereby posts this troubleshooting chart for [TERUMO INFUSION PUMP  MODEL STC-508].
In most cases, it has been adviced to replace the board as card basis; but can be repaird , if you have skill and experience in repairing electronic circuit boards.  Consider this chart as guide to locate the faulty board.  If the board is found to be irreparable, replace the board.
PART-1
TROUBLESHOOTING CHART: TERUMO INFUSION PUMP: STC – 508 

NO	CAUSE	HOW TO CHECK	WHAT TO DO
1	wiring lead in contact with, or foreign matter caught in movable part of occlusion detector I.V solution stains on unit	Visual check Visual check	Correct the wiring Wipe off I.V solution with warm water
2	Unit not plugged into outlet, or power cord defective. Fuse blown [inside the inlet] Transformer defective CN-9 of main CPU connections bad. Fuse blown inside main PCB: ICP 2 Rectifier defective [inside main PCB:PS1]. Three terminal regulator damage.  (radiating fin part: SI3132V) LED defective (inside sub PCB: LED 1)	AC voltage not being received at service outlet Visual check on 2 fuses at the back.  Tester check. Check potential difference between No-4 and No-6 pins of CN-9.  If 13.8VAC voltage is not measured , suspect transformer defective Check connector Check fuse: ICP 2, applying tester between two ends of fuse. Check potential difference between NO-1 & No-2 pins of CN-12. If about 17VDC voltage is not measured, suspect regulator defective. Check the potential difference between NO-3 & No-2 pins of CN-12.  If about 13VDC voltage is not measured suspect regulator defective. Check the voltage between the 2 ends of resistance R1.  If it is 0 or 13V suspect LED defective.	Secure plug-receptacle connection.  Replace power source cable for supply. replace fuse (315mA or 500mA slow blow type) Check transformer relevant wiring: replace transformer. Repair connector Replace main PCB. Replace main PCB. Replace radiating fin. Replace sub PCB.
2	9. Short-circuit of wiring.	9. Check voltage between input/output ends of three terminal regulator and ground by tester.	9.  Replace main PCB or sub PCB.
3	Membrane sheet SW defective. Cable defective. Power supply circuit defective. Three terminal regulator for 5V output defective (Radiating fin part: SI 3052V) Short circuit	Self- check (*10) does not start. Suspect the membrane sheet SW defective when: circuit between No-6 & No-10 pins of sub PCB connector (CN-1) remains open when power source SW is pressed, or it is in short circuit condition before SW operation. Check cable by applying tester between No 12 pin of sub PCB (CN-2) and No 6 pin of main PCB (CN3B). Check if II level signal is output to No 12 pin of power source circuit IC7.  Also No 1 pin of source power ON/OFF relay is on L level.  Check if voltage between No-7 and No-8 pins of CN-12 is measured at about 13VDC. Suspect regulator defective when: about 13VDC voltage is measured between No-7 & No-8 of pins of CN-12, but 5VDC is not measured between No-9 & No8 pins Tester check between input/output ends of three terminal regulator and ground.	Replace panel part. Replace cable. Replace main PCB. Replace rear panel. Replace main PCB or Sub.
4	Sub PCB, ROM, RAM defective Main PCB, ROM, RAM defective	Err-1 is displayed. Err-2 is displayed	Replace sub PCB. Replace main PCB.
5	Main CPU defective Motor drive circuit defective. Main PCB connector: CN-5 defective. Main PCB connector CN5 defective Cable defective. Motor defective Cable defective. Motor rotation detection sensor defective. Defective motor rotation detection circuit.	Err-3 is displayed. Suspect main CPU. When signal is not generated on main CPU pins 36-43 or, when signal is generated but pulse dignal is input also to main CPU NO.1 pin. Suspect motor drive circuit defective: when signal is output on on main CPU pins No 367-43, but voltage is ot measured on pins no.1 and No-1 of the connector CN-5 or pulse dignal is not generated on pins 2-5 Check connector. Check connector. Check cable. Motor is out of order when:  signal is generated on main CPU pins 36-43 AND voltage is measure on pins No-1 and No-6 of connector: CN-5 and pulse signal is generated on pins 2-5. Check cable. Suspect sensor.  Defective when: pulse signal is not output between No-3 and No-4 pins of connector CN11 during motor is running. Suspect circuit defective when: Pulse signal is not output from No-10 pin of IC-12 of motor rotation detection circuit during motor is running.	Replace main PCB. Replace Main PCB. Check connector. Check connector function. Replace cable Replace motor. Replace cable. Replace motor rotation detection sensor. Replace main PCB.
6	Main PCB connector: CN-4 defective. Cable defective. Air-in-line detection circuit defective. Supersoniv air-in-line detection sensor defective. Main CPU defective. Main PCB connector: CN-6 defective. Cable defective. Occlusion detection PCB defective. Main CPU defective.	Err 4 is displayed. Check connector. Check cable. Check if oscillator (QZ2) oscillates at 3.2MHz. Check if 1.6MHz pulse in output fron No-3 pin of IC10 of air-in-line detection circuit.  Check if there is 1.6MHz transmitting pulse between No-1 and No-2 pins of connector CN-4.  Check if there is 1.6MHz receiving pulse between No-4 and No-5 pins of connector CN-4.  Check if amplified recived signal is output frm NO-14 pin of IC-15 of air-in-line detection circuit.  Check if voltage is measured on N)-16 pin of main CPU: (IC-1) exceeding threshold value [0.8v] Suspect sensor defective: when Wave receiving pulse signal is not output from pins No-4, No-5 of CN-4.  despite wave transmitting pulse is input to pins No-1 and No-2 of connector [CN-4]. Suspect main CPU failure when: voltage is measured on No-16 pin of main CPU:[IC-1] exceeding threshold value of [0.8V]and, at the same time 5V voltage is added to pin No-12. Check connector. Check cable. Occlusion detection PCB id judged to be out of order, if voltage between N0-3 and No-4 pins does not change when occlusion frame is forced to move by finger. Suspect main CPU defective when: voltage is measured on No-16 pin of main CPU (IC-1) not exceeding threshold value [1.0V] and at the same time 5V voltage is added to pin No-12.	Check connector. Replace cable. Replace main PCB. Replace supersonic air-in-line detection sensor. Replace main PCB. Check connector. replace cable. Replace occlusion detection PCB. Replace main PCB
7	E2-ROM errir	1. ERR 5 is displayed	1.  Replace main PCB.
8	Main PCB connector: CN-3 defective. Main or sub PCB defective Communication circuit defective.	Err 6,7 display or buzzer ON. Check connector. Err 6,7 display or buzzer ON. Err 6,7 display or buzzer ON.	check connector. Replace main of sub PCB. Replace main or sub PCB. [Note]: Err display/buzzer On occurs also at time of DIP SW 8bit ON.(fall edge of timing chart.)
9	Other switch is also ON. Sub PCB connector (CN-1) defective. Membrane sheet SW defective. Sub CPU defective	Err 8 is displayed Err 8 display. Check connector. Membrane SW is damaged when the following connector pins are ins short-circuit from the beginning [before SW ON]             [CN-1]: 5-7P, 5-8P,5-9P, 2-7P, 2-8P, 2-9P, 3-7P, 3-8P, 3-9P, 4-8P, 4-9P. Other than the above.	Power source re-switch ON. Check connector function. Replace panel part. Replace sub PCB.
10	Sub PCB connector: CN-1 defective. Cable defective. Membrane sheet SW defective. Defective of source power SW disconnection detection circuit. Sub CPU defective.	Err 9 is displayed. Check connector. Check cable. Membrane SW is damaged when No-6 and No-10 pins of CN-1 of PCB are continuously in short circuit. Circuit is defective when: Output from No-42 pin of sub CPU continues on H level, despite membrane SW is normal. Other than the above.	Check connection function. Replace cable. Replace membrane sheet SW. Replace sub PCB. Replace sub PCB.

TO BE CONTINUED  TO PART-2