Page 2049 of 4133
Fig. 9: Checking Generator Output (Chassis 163)
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 15 © 2006 Mitchell Repair Information Company, LLC.
Page 2050 of 4133
VOLTAGE REGULATOR CONTROL
1. Connect multimeter. See Fig. 10 . Ensure charge indicator light goes out when engine is idling and with
increasing engine speed up to 3000 RPM. Apply load to battery by turning on headlights and noting
reading after 2 minutes.
2. Voltage reading should be 13-14.5 volts. If voltage is not to specification, replace voltage regulator. See
VOLTAGE REGULATOR
under REMOVAL & INSTALLATION. If regulator is okay, replace
generator. See GENERATOR under REMOVAL & INSTALLATION.
2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 16 © 2006 Mitchell Repair Information Company, LLC.
Page 2051 of 4133
Fig. 10: Checking Voltage Regulator (Chassis 163)
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
DIODE TEST
2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 17 © 2006 Mitchell Repair Information Company, LLC.
Page 2052 of 4133
Connect DC clip-on probe from engine tester with oscilloscope to positive battery terminal. See Fig. 11. Start
engine. Switch on low beam. Access diode test at 3000 RPM. See Fig. 12
-Fig. 14 . Replace generator as
necessar
y.
2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 18 © 2006 Mitchell Repair Information Company, LLC.
Page 2053 of 4133
2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 19 © 2006 Mitchell Repair Information Company, LLC.
Page 2054 of 4133
Fig. 11: Identifying Oscilloscope Connection
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Fig. 12: Identifying Oscilloscope Patterns (No Fault Indicated)
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 20 © 2006 Mitchell Repair Information Company, LLC.
Page 2055 of 4133
Fig. 13: Identifying Oscilloscope Patterns (Positive Diode Defective)
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 21 © 2006 Mitchell Repair Information Company, LLC.
Page 2056 of 4133
Fig. 14: Identifying Oscilloscope Patterns (Negative Diode Defective)
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
REMOVAL & INSTALLATION
GENERATOR
Removal & Installation (Model 163)
Disconnect and shield negative battery cable. Remove air cleaner housing. Remove engine trim panel. Remove
"V" belt b
y swiveling tensioning pulley and holding in place with a drift. Disconnect generator B+ electrical
NOTE: Numbers in text refer to numbers in figures.
2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 22 © 2006 Mitchell Repair Information Company, LLC.