Test charging current for alternator (Engine 272, 273, 642, 629) - AR15.40-P-5011GA

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ENGINE 272, 273, 642, 629 in MODEL 164

Connection scheme

Fig 1: Alternator Charging Current Connection Diagram

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

	Checking
	Risk of explosion caused by oxyhydrogen gas. Risk of poisoning and caustic burns caused by swallowing battery acid. Risk of injury caused by burns to skin and eyes from battery acid or when handling damaged lead-acid batteries	No fire, sparks, open flames or smoking. Wear acid-resistant gloves, clothing and goggles. Only pour battery acid into suitable and appropriately marked containers.	AS54.10-Z-0001-01A
	Notes on battery		AH54.10-P-0001-01A
1	Check tension of poly-V belt
2	Check poly-V belt for wear
	Check visible area of poly-V belt for wear	Model 164.1 with engine 272.9, 164.8 with engine 273.9	AP13.22-P-1352GZC
		Model 251.065/165	AP13.22-P-1352RTC
		Model 164 with engine 629	AP13.22-P-1352GZE
		Model 164 with engine 642	AP13.22-P-1352GZD
		Model 251.020/022/122 Model 164.1 with engine 273.9, 251.026/ 054/056/072/126/154/156/172	AP13.22-P-1352RTD
3	Check electrical lines at battery (G1), alternator (G2) and starter (M1)	Tight seating and proper condition of the cables must be guaranteed.
4.1	Remove lower engine compartment paneling	Model 164 with engine 272, 273	AR61.20-P-1105GZ
		Model 251 with engine 272, 273	AR61.20-P-1105RT
4.2	Remove bottom section of soundproofing	Model 164 with engine 629, 642	AR94.30-P-5300GZ
		Model 251 with engine 642	AR94.30-P-5300RT
5	Check ground strap between engine and body for tight seating and proper condition
6	Connect volt-ampere tester (079) with current clamp (065) according to the connection diagram
	Risk of accident caused by vehicle starting off by itself when engine is running. Risk of injury caused by contusions and burns during starting procedure or when working near the engine as it is running	Secure vehicle to prevent it from moving by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.	AS00.00-Z-0005-01A
7	Start engine
8	Load battery (G1) with volt ampere tester (079) and check charging current of alternator (G2) with increased engine speed	Vary load resistance long enough until maximum load current is achieved; when this is done, the regulating voltage must not drop below 12.7 V. Engine 272, 273
		Charge current for alternator Engine 629	*BE15.40-P-1001-01I
		Charge current for alternator Engine 642	*BE15.40-P-1001-01J
		Charge current for alternator Charging current below desired value: ↓	*BE15.40-P-1001-01H
		Check diodes of alternator. If diodes are faulty: ↓ Remove/install alternator	AR15.40-P-9301-02GZ
		Model 164 with engine 272, 273	AR15.40-P-5032GZA
		Model 251 with engine 272, 273	AR15.40-P-5032RTA
		Model 164 with engine 629	AR15.40-P-5032GZD
		Model 164, 251 with engine 642	AR15.40-P-5032GZB
9	Turn off engine
10	Disconnect volt ampere tester (079) with current clamp (065)
11.1	Install lower engine compartment paneling	Model 164 with engine 272, 273	AR61.20-P-1105GZ
		Model 251 with engine 272, 273	AR61.20-P-1105RT
11.2	Install bottom sections of soundproofing	Model 164 with engine 629, 642	AR94.30-P-5300GZ
		Model 251 with engine 642	AR94.30-P-5300RT

CHECK VALUES FOR ALTERNATOR

Number	Designation			Engine 629 in model 164, 211, 221
BE15.40-P-1001-01J	Charge current for alternator	max.	A	220
		min.	A	170
		Engine speed	RPM	2000
		Ratio	i=	2.93

CHECK VALUES FOR ALTERNATOR

Number	Designation			Engine 642 in model 164, 203, 209, 211, 251, Valeo	Engine 642 in model 164, 221, 251, Bosch
BE15.40-P-1001-01H	Charge current for alternator	max.	A	180	220
		min.	A	140	170
		Engine speed	RPM	2200	2000
		Ratio	i=	2.82	2.93

CHECK VALUES FOR ALTERNATOR

Number	Designation			Engine 272 in model 164, 211, 219, 230, 251 Engine 272 in model 221 without code 910	Engine 273 in model 164, 209, 211, 219, 230, 251 Engine 273 in model 216, 221 without code 910
BE15.40-P-1001-01I	Charge current for alternator	max.	A	180	180
		min.	A	140	140
		Engine speed	RPM	2000	2000
		Ratio	i=	2.93	2.93