Brother BAS-311G service manual Electrical Mechanism, 5088Q, 5089Q, 4892Q

8. ELECTRICAL MECHANISM

Problem		#22	Thread wiper does not operate.
		Cause		Inspection/Remedy/Adjustment	Replacement if a malfunction
1.	Incorrect mechanism adjustment			Adjust the thread wiper while referring to “7-11.
				Adjusting the thread wiper”.
				(If it is clear that the thread wiper mechanism is
				not operating, carry out inspections 2. and 3.
				below.)
2.	Poor connector contact			Check that connector P1 (MAIN) is inserted into
				the PMD P.C. board.
3.	Malfunction		of thread wiper	Disconnect connector P6 (SOL1) from the PMD	Thread wiper solenoid
	solenoid			P.C. board, and measure the resistance between
				pins 2-5 of the cord-side connector.
				OK if approximately 4 Ω
			5088Q
4.	Malfunction of PMD P.C. board			With connector P6 (SOL1) connected to the	PMD P.C. board
				PMD P.C. board, turn on the power and carry out
				sewing, and measure the voltage between pins
				2-5 of connector P6 (SOL1).
				OK if voltage is output momentarily at the sewing
				end.
			5089Q
Problem		#23	Needle does not stop in the up position ([E110] is displayed.)
		Cause		Inspection/Remedy/Adjustment	Replacement if a malfunction
1.	Incorrect adjustment			Adjust while referring to “7-21. Adjusting the
				needle up stop home position” and “7-22.
				Adjusting the needle up stop position”.
2.	Malfunction of synchronizer			Refer to inspection #19.
3.	Malfunction of cord			Refer to inspection #18.
4.	Malfunction		of power supply	With connector P2 (POWER2) connected to the	Power supply motor P.C.
	motor P.C. board			PMD P.C. board, measure the voltage at the cord.	board
				OK if approximately 30 V DC between pins 3-4
			4892Q
5.	Malfunction of main P.C. board				Main P.C. board
6.	Malfunction of motor				Motor

136 BAS-311G, BAS-326G