Check regulator and alternator - AR15.40-P-5000CW

ENGINE 156, 271, 272, 273, 274, 276, 278, 642, 651 in MODEL 212 

ENGINE 156, 271, 272, 274, 642, 646, 651 in MODEL 204 

ENGINE 271, 272, 273, 642, 651 in MODEL 207 

ENGINE 271, 651 in MODEL 172 

ENGINE 274, 651 in MODEL 218 

ENGINE 651 in MODEL 166 

ENGINE 651 in MODEL 221 

Shown on model 212.002 

Fig 1: Checking Regulator And Alternator

Courtesy of MERCEDES-BENZ USA

	Check
	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
1	Check condition of on-board electrical system battery	ENGINE 651 in MODEL 166	AR54.10-P-1129GZ
		ENGINE 271, 651 in MODEL 172	AR54.10-P-1129V
		MODEL 204 with ENGINE 156, 271, 272, 274, 642, 646, 651 MODEL 207 with ENGINE 271, 272, 273, 642, 651 MODEL 212 with ENGINE 156, 271, 272, 273, 274, 276, 278, 642, 651 MODEL 218 with ENGINE 274, 651	AR54.10-P-1129CW
		MODEL 221.0/1 up to 6/1/08 with ENGINE 651 without CODE 809 (Model year 2009)	AR54.10-P-1129SX
		MODEL 221.0/1 as of 6/2/08 with ENGINE 651 with CODE 809 (Model year 2009)	AR54.10-P-1129SY
2	Attach diagnostic system (0100) at diagnostic connector (X11/4)
			AD00.00-P-2000-04A
3	Start engine	Only perform tests when engine is at its normal operating temperature.
4	Check alternator with diagnostic system (0100)	Tests are menu-assisted: Control unit → Actuations → Alternator diagnosis
5	Turn off engine
6	Disconnect diagnostic system (0100)
			AD00.00-P-2000-04A