Test charging current for alternator - AR15.40-P-5011GA: Notes

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ENGINE 272, 273, 642, 629 in MODEL 164

Connection scheme

Fig 1: Alternator And 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		AP13.22-P-1352GZD
3	Check electrical lines at battery (G1), alternator (G2) and starter (M1)	Tight seating and proper condition of the cables must be guaranteed.
4	Remove bottom section of soundproofing		AR94.30-P-5300GZ
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	*BE15.40-P-1001-01I
		Engine 629
		Charge current for alternator	*BE15.40-P-1001-01J
		Engine 642
		Charge current for alternator	*BE15.40-P-1001-01H
		Charging current below desired value: ↓
		Check diodes of alternator.	AR15.40-P-9301-02GZ
		If diodes are faulty: ↓
		Remove/install alternator	AR15.40-P-5032GZB
9	Turn off engine
10	Disconnect volt ampere tester (079) with current clamp (065)
11	Install bottom sections of soundproofing		AR94.30-P-5300GZ

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, 19, 30, 251 Engine 272 in model 221 without code 910	Engine 273 in model 164, 209, 211, 219, 230, 251, 463 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