ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of commands87G
87G - 87V7 MR-372-J84-87G050$770.mif
UPC
Vdiag No.: 48, 4C
AC014
ALTERNATOR REGULATION
NOTESConditions for the application of the command:
–engine running at idling speed and warm engine,
–air conditioning off,
–check that the passenger compartment blower unit is not operating.
–check that the cooling fan assemblies are not operating,
–if fault DF007 UPC-alternator connection is declared present, deal with this fault
first,
–check the conformity of PR010 Alternator charge (see Interpretation of
parameters).
Effect of command:
–for 30 seconds, the Protection and Switching Unit sets the alternator a regulation
voltage of 15 V ± 0.5,
–then for another 30 seconds, the Protection and Switching Unit imposes a
regulation voltage of 13 V ± 0.5 on the alternator.
Switch off all the electrical consumers (fans, main beam headlights, etc.).
Measure the voltage across the alternator terminals, between the B+ terminal and the alternator chassis earth.
Run AC014 Alternator regulation.
Wait 20 seconds,
For 10 seconds the alternator voltage should be 15 V ± 0.5.
Wait 20 seconds,
For 10 seconds the alternator voltage should be 13 V ± 0.5.
Switch on the heated rear screen and the main beam headlights.
Run AC014 again.
Wait 20 seconds,
For 10 seconds the alternator voltage should be 15 V ± 0.5.
Wait 20 seconds,
For 10 seconds the alternator voltage should be 13 V ± 0.5.
If the values obtained are not correct, replace the alternator (see MR 364 or MR 370 Mechanical, 16A, Starting-
Charging, Alternator: Removal - Refitting).
AFTER REPAIRRepeat the conformity check from the start.
