Test Alternator Charging Current - AR15.40-S-5011E

Model 447 with engine 274, 622, 651, 654 

Model 448 with engine 274 

Model 900 with engine 651 

Model 906 with engine 271, 272, 642, 651.9 

Model 907 with engine 274, 642, 651, 654 

Model 910 with engine 651, 654 

Shown in connection scheme for model 447 

Courtesy of MERCEDES-BENZ USA

	Risk of accident  from vehicle starting off by itself when engine running. Risk of injury  (bruises and burns) resulting from working on the engine while it is being started or when it is running.	Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.	AS00.00-Z-0005-01A
	Check
1	Check preconditions for alternator test and ensure they are met.		AR15.40-S-5009E
2	Check the alternator's charging voltage (G2).		AR15.40-S-5010E
3	Attach the multimeter (003) with DC clip-on probe (065) to the alternator's electric line (G2) according to the connection scheme.
4	Attach the load tester (079) to the on-board electrical system battery (G1) according to the connection scheme.
	000 588 31 19 00 Load tester		WS15.00-P-0077B
5	Start engine.
6	Check the alternator's (G2) charging current.	Check the charging current at higher rpms, during which the on-board electrical system battery (G1) is put under load with the load tester (079). Change the load resistance until the maximum charging current, according to design of the ALT (G2), is reached. In doing so the charging voltage must not fall below 12.7 V. If the maximum charging current is not reached, ↓ Check alternator diodes (G2).	AR15.40-S-9301-02E
7	Switch off engine.
8	Remove the multimeter (003) with the DC clip-on probe (065).
9	Remove the load tester (079).