Chrysler 2005 Crossfire SRT6 Service Manual page 4304

ZH EMISSIONS CONTROL 25 - 11
OPERATION
OPERATION - SYSTEM
The Powertrain Control Module (PCM) monitors many different circuits in the fuel injection, ignition, emission and
engine systems. If the PCM senses a problem with a monitored circuit often enough to indicate an actual problem,
it stores a Diagnostic Trouble Code (DTC) in the PCM's memory. If the code applies to a non-emissions related
component or system and the problem is repaired or ceases to exist, the PCM cancels the code after 40 warmup
cycles. Diagnostic trouble codes that affect vehicle emissions illuminate the Malfunction Indicator Lamp (MIL).
Certain criteria must be met before the PCM stores a DTC in memory. The criteria may be a specific range of
engine RPM, engine temperature, and/or input voltage to the PCM.
The PCM might not store a DTC for a monitored circuit even though a malfunction has occurred. This may happen
because one of the DTC criteria for the circuit has not been met. For example , assume the diagnostic trouble code
criteria requires the PCM to monitor the circuit only when the engine operates between 750 and 2000 rpm. Suppose
the sensor's output circuit shorts to ground when the engine operates above 2400 rpm (resulting in 0 volt input to
the PCM). Because the condition happens at an engine speed above the maximum threshold (2000 rpm), the PCM
will not store a DTC.
There are several operating conditions for which the PCM monitors and sets DTCs. Refer to Monitored Systems,
Monitored Components, and Non-Monitored Circuits in this section.
Note: Various diagnostic procedures may actually cause a diagnostic monitor to set a DTC. For instance,
pulling a spark plug wire to perform a spark test may set the misfire code. When a repair is completed and
verified, use the DRB III scan tool to erase all DTCs and extinguish the MIL.
Technicians can retrieve stored DTCs. For obtaining
the DTC information, use the Data Link Connector (2)
with the DRB III scan tool.
OPERATION - SYSTEM
The Powertrain Control Module (PCM) monitors many different circuits in the fuel injection, ignition, emission and
engine systems. If the PCM senses a problem with a monitored circuit often enough to indicate an actual problem,
it stores a Diagnostic Trouble Code (DTC) in the PCM's memory. If the code applies to a non-emissions related
component or system and the problem is repaired or ceases to exist, the PCM cancels the code after 40 warmup
cycles. Diagnostic trouble codes that affect vehicle emissions illuminate the Malfunction Indicator Lamp (MIL).
Certain criteria must be met before the PCM stores a DTC in memory. The criteria may be a specific range of
engine RPM, engine temperature, and/or input voltage to the PCM.
The PCM might not store a DTC for a monitored circuit even though a malfunction has occurred. This may happen
because one of the DTC criteria for the circuit has not been met. For example , assume the diagnostic trouble code
criteria requires the PCM to monitor the circuit only when the engine operates between 750 and 2000 rpm. Suppose
the sensor's output circuit shorts to ground when the engine operates above 2400 rpm (resulting in 0 volt input to