Multiquip ST-45HRM CE Electrical System Troubleshooting, Symptom, Possible Problem, Solution

ST-45HRM CE CONCRETE PUMP—TROUBLESHOOTING (ELECTRICAL

Practically all breakdowns can be prevented by proper handling and maintenance inspections, but in the event of a breakdown, please take a remedial action following the diagnosis based on the Electrical System Troubleshooting (Table 16) information shown below and on the proceeding page. If the problem cannot be remedied, please leave the unit just as it is and consult our company's business office or service plant.

TABLE 16. ELECTRICAL SYSTEM TROUBLESHOOTING

SYMPTOM	POSSIBLE PROBLEM	SOLUTION
		If the hydraulic system is in a maximum pressure condition, pull
After completion of a pumping stroke,		the toggle on the emergency cycle switch (located inside the
	Proximity switch is not emitting a radio	control box) towards you. If the pump cycles, replace the proximity
pumping pressure gauge indicates
	frequency?	switch at the lubrication box. If the pump cycles when you push
high pressure and cycle stops.
		the toggle down, replace the proximity switch on the towing end of
		the pump.
		Use a hot jumper wire. Connect (jumper wire) to terminals #35
Emergency cycle switch does not	Faulty K-4 relay?	and #36 on terminal block #1. When contact is made between
cycle pump		these two terminals and the pump cycles. This would indicate that
		you have a faulty K-4 relay.
Starter switch is activated and pump		Check fuse box in control panel. Replace blown fuses.
	Faulty fuses?
does not start		Check fuse link below engine solenoid, next to batter.
Hatz engine will not continue to run	D-1 diode has failed?	Check D1 diode in control box. Replace if needed with 6 amp
after key is released		diode P/N EGG5815 or equivalent.
Hatz engine will not start	No power to TB-5, conductor #3?	Check and replace K1 relay if necessary
	No power to magnet valve start/stop?
Engine runs, but no current travels to	Faulty K-2 relay?	Check and replace K-2 relay if necessary
circuits #32-47
When pump is turned on, engine	K-6 relay not completing the circuit?
		Check and replace K-6 relay if necessary
RPM's will not increase	Open circuit at TB1-24?
The pump will not reverse when	K-5 relay failure?	Check and replace K-5 relay if necessary
operated by remote control
Engine oil pressure light will not	Oil pressure sending unit failure?	Check and replace sending unit if necessary
de-activate
	Faulty D-2 diode?	Replace with diode 1U404-C
Battery charge light wont de-activate
	Alternator not charging battery?	Check and repair/replace alternator unit.

MAYCO ST-45HRM CE PUMP — OPERATION & PARTS MANUAL — REV. #0 (02/23/04) — PAGE 69