1451-01
2) Troubleshooting for Alternator
Item Cause Action
Overcharged batteryDefective alternator voltage regulator
Replace the alternator
Defective voltage detection wiring Repair or replace
Loose alternator drive belt Adjust the belt tension or replace
Discharged batteryPoor connection of related circuit or open
circuitRetighten the loose connection or
repair open circuit
Defective alternator voltage regulator
Replace the alternator
Defective alternator voltage regulator
Replace the alternator
Terminated battery Replace the battery
Defective ground Repair
Charge warning
lamp does not come
on when turning on
ignition switch with
engine stoppedDefective alternator voltage regulator
Replace the alternator
Open circuit in charge warning lamp, fuse
or wiringReplace or repair the charge warning
lamp or fuse
Defective ignition switch Replace the ignition switch
Defective ground of alternator circuit Repair
Charge warning
lamp is not turned
off after starting
engineDefective alternator voltage regulator
Replace the alternator
Corroded or worn battery cableRepair or replace the battery cable
Loose alternator drive belReplace the batteryAdjust the belt
tension or replace the belt
Defective wiring harness Repair or replace
0000-00
This is done periodically under certain operating conditions. When the resetting is finished, the new
minimum pulse value replaces the value obtained during the previous resetting. The first MDP value is
provided by the C3I. Each resetting then allows the closed loop of the MDP to be updated according to
the deviation of the injector.
B. Detection of leaks in the cylinders
The accelerometer is also used to detect any injector which may have stuck open. The detection
principle is based on monitoring the ratio. If there is a leak in the cylinder, the accumulated fuel self-
ignites as soon as the temperature and pressure conditions are favorable (high engine speed, high load
and small leak).
This combustion is set off at about 20 degrees before TDC and before main injection.
The ratio therefore increases considerably in the detection window. It is this increase which allows the
leaks to be detected. The threshold beyond which a fault is signaled is a percentage of the maximum
possible value of the ratio.
Because of the severity of the recovery process (engine shut-down), the etection must be extremely
robust.
An increase in the ratio can be the consequence of various causes:
Pilot injection too much
Main combustion offset
Fuel leak in the cylinder -
-
-
If the ratio becomes too high, the strategy initially restricts the pilot injection flow and retards the main
injection. If the ratio remains high despite these interventions, this shows that a real leak is present, a
fault is signaled and the engine is shut down.
C. Detection of an accelerometer fault
This strategy permits the detection of a fault in the sensor or in the wiring loom connecting the sensor to
the ECU.
It is based on detection of the combustion. When the engine is idling, the detection window is set too low
for the combustion caused by the main injection. If the ratio increases, this shows that the knock sensor
is working properly, but otherwise a fault is signaled to indicate a sensor failure. The recovery modes
associated with this fault consist of inhibition of the pilot injection and discharge through the injectors.