Dodge ZB 2005 Service Manual page 1131

GENERAL INFORMATION
Cylinder Compression − The PCM cannot de-
tect uneven, low, or high engine cylinder compres-
sion.(*)
Excessive Oil Consumption − Although the
PCM monitors the exhaust oxygen content through
the oxygen sensor when the system is in a closed
loop, it cannot determine excessive oil consumption.
NOTE: Any of these conditions could result
in a rich or lean condition causing an oxygen
sensor trouble code to be stored in the PCM,
or the vehicle may exhibit one or more of the
driveability symptoms listed in the Table of
Contents.
3.3 DIAGNOSTIC TROUBLE CODES
Each diagnostic trouble code is diagnosed by
following a specific testing procedure. The diagnos-
tic test procedures contain step-by-step instructions
for determining the cause of trouble codes as well as
no trouble code problems. It is not necessary to
perform all of the tests in this book to diagnose an
individual code. Always begin by reading the diag-
nostic trouble codes using the DRBIII .
3.3.1 HARD CODE
A diagnostic trouble code that comes back within
one cycle of the ignition key is a "hard" code. This
means that the problem is present when the PCM
checks that circuit or function. Procedures in this
manual verify if the trouble code is a hard code at
the beginning of each test. When it is not a hard
code, an "intermittent" test must be performed.
Codes that are for OBDII monitors will not set
with just the ignition key on. Comparing these to
non-emission codes, they will seem like an intermit-
tent. These codes require a set of parameters to be
performed (The DRBIII pre-test screens will help
with this for MONITOR codes), this is called a
"TRIP". All OBDII DTCs will set after two or in
some cases one trip failures, and the MIL will be
turned on. These codes require three successful, no
failures, TRIPS to extinguish the MIL, followed by
40 warm-up cycles to erase the code. For further
explanation of TRIPS, Pre-test screens, Warm-up
cycles, and the use of the DRBIII , refer to the On
Board Diagnostic training booklet #81-699-97094.
3.3.2 INTERMITTENT CODE
A diagnostic trouble code that is not present every
time the PCM checks the circuit is an "intermittent"
code. Most intermittent codes are caused by wiring
or connector problems. Intermittent conditions that
come and go like this are the most difficult to
diagnose; they must be looked for under specific
conditions that cause them. The following proce-
dures may assist you in identifying a possible
intermittent problem:
•
Visually inspect related wire harness connectors.
Look for broken, bent, pushed out, or corroded
terminals.
• Visually inspect the related harnesses. Look for
chafed, pierced, or partially broken wire.
• Refer to any S.T.A.R. Hotline Newsletters or
technical service bulletins that may apply.
• Use the DRBIII data recorder or co-pilot.
3.3.3 STARTS SINCE SET COUNTER
This reset counter counts the number of times the
vehicle has been started since codes were last set or
erased. This counter will count up to 255 start
counts. The number of starts helps determine when
the trouble code actually happened. This is recorded
by the PCM and can be viewed on the DRBIII as
STARTS since set. When there are no trouble codes
stored in memory, the DRBIII will display "NO
TROUBLE CODES FOUND" and the reset counter
will show "STARTS since set = XXX." OBDII vehi-
cles will also display a DTC Specific or Global "Good
Trip" counter which will indicate the number of
"Good Trips" since the DTC was set. After 3 consec-
utive "Good Trips," the MIL is extinguished and the
good trip counter is replaced by a "Warm Up Cycle"
counter. 40 Warm-up Cycles will erase the DTC and
Freeze Frame information.
3.3.4 NO START INFORMATION
IMPORTANT NOTE:
If the Powertrain Control Module has been pro-
grammed, a DTC will be set in the ABS and Air Bag
modules. In addition, if the vehicle is equipped with
a Sentry Key Immobilizer Module (SKIM), Secret
Key data must be updated to enable starting.
FOR ABS AND AIR BAG SYSTEMS:
1. Enter correct VIN and Mileage in PCM.
2. Erase codes in ABS and Air Bag modules.
FOR SKIM THEFT ALARM:
1. Connect the DRBIII to the data link connector.
2. Go to Theft Alarm, SKIM, Misc. and place the
SKIM in secured access mode, by using the
appropriate PIN code for this vehicle.
3. Select Update the Secret Key data, data will be
transferred from the SKIM to the PCM (This is
required to allow the vehicle to start with the
new PCM).
4. If three attempts are made to enter secured
access mode using the incorrect PIN, secured
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