2000 CHRYSLER CARAVAN Service Manual

After-Run- When fused ignition switch output is removed from the ECM cavity 47, the ECM
performs a self-diagnostic check in the following order:
1. Electrical shut-off test
2. Fuel quantity actuator test
3. Monitoring module test
4. Voltage regulator test
5. Main relay test (if tests 1-4 pass)
If any of tests 1-4 fail, the fault is stored in memory, and can be retrieved during the next ignition
cycle using the DRB.
3.2.3 Monitored Circuits
The ECM is able to monitor and identify most driveability related trouble conditions. Some circuits
are directly monitored through ECM feedback circuitry. In addition, the ECM monitors the voltage
state of some circuits and compares those states with expected values. Other systems are
monitored indirectly when the ECM conducts a rationality test to identify problems.
Although most subsystems of the powertrain control module are either directly or indirectly
monitored, there may be occasions when diagnostic trouble codes are not immediately identified.
For a trouble code to set, specific conditions must be met and unless these conditions are
encountered, a code will not set.
3.2.4 SKIS On-Board Diagnostics
The SKIS module has been programmed to transmit and monitor many different coded messages
as well as CCD Bus messages. This monitoring is called ``On-Board Diagnosis''.
Certain criteria must be met for a diagnostic trouble code to be entered into the Sentry Key
Immobilizer Module (SKIM) memory. The criteria may be a range of: input voltage, CCD Bus
messages, or coded messages to the SKIM. If all of the criteria for monitoring a circuit or function
are met and a fault is sensed, a diagnostic trouble code will be stored in the SKIM memory.
3.2.5 SKIS Overview
The Sentry Key Immobilizer System (SKIS) is an immobilizer system designed to prevent
unauthorized vehicle operation. The system consists of a Sentry Key Immobilizer Module (SKIM),
ignition key(s) equipped with a transponder chip, engine controller and body controller. When the
ignition switch is turned on, the SKIM interrogates the ignition key. If the ignition key is ªValidº the
SKIM sends a CCD Bus message to the body controller indicating the presence of a valid ignition
key. The BCM then supplies the ECM with a valid immobilizer signal allowing the engine to
continue to operate.
3.2.6 SKIS Operation
When ignition power is supplied to the SKIM, the SKIM performs an internal self-test. After the
self-test is completed, the SKIM energizes the antenna (this activates the transponder chip) and
sends a challenge to the transponder chip. The transponder chip responds to the challenge by
generating an encrypted response message using the following:
Secret Key þ This is an electronically stored value (identification number) that is unique to each
SKIS. The secret key is stored in the SKIM, BCM and all ignition key transponders.
Challenge þ This is a random number that is generated by the SKIM at each ignition key cycle.
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The secret key and challenge are plugged into an algorithm that produces the encrypted response
message. The transponder uses the crypto algorithm to receive, decode and respond to the
message sent by SKIM. After responding to the coded message, the transponder sends a
transponder I.D. message to the SKIM. The SKIM compares the transponder I.D. to the available
valid key codes in SKIM memory (8 key maximum). After validating the key the SKIM sends a
CCD Bus message called a ªSeed Requestº to the body controller then waits for a body controller
response. If the body controller does not respond, the SKIM will send the seed request again.
After three failed attempts the SKIM will stop sending the seed request and store a trouble code.
If the body controller sends a seed response, the SKIM sends a valid/invalid key message to the
body controller. This is an encrypted message that is generated using the following:
VIN þ Vehicle Identification Number
Seed þ This is a random number that is generated by the BCM at each ignition key cycle.
The VIN and seed are plugged into a rolling code algorithm that encrypts the ªvalid/invalid keyº
message. The body controller uses the rolling code algorithm to receive, decode and respond to
the valid/invalid key message sent by SKIM. After sending the valid/invalid key message the SKIM
waits 3.5 seconds for a PCM status message from the body controller. If the BCM does not
respond with a valid key message to the SKIM, a fault is detected and a trouble code stored.
The SKIS incorporates a warning (``ALARM SET'') lamp located in the message center. The lamp
receives switched ignition voltage and is hardwired to the body controller. The lamp is actuated
when the SKIM sends a CCD Bus message to the body controller requesting the lamp on. The
body controller then provides the ground for the lamp. The SKIM will request lamp operation for
the following:
± ± bulb check at ignition on
± to alert the vehicle operator to a SKIS malfunction
For all faults except transponder faults and VIN mismatch, the lamp remains on steady. In the
event of a transponder fault the light flashes at the rate of 1Hz (once per second). If a fault is
present the lamp will remain on or flashing for the complete ignition cycle. If a fault is stored in
SKIM memory which prevents the system from operating properly, the ECM will allow the engine
to start and run (for 2 seconds) up to six times. After the sixth attempt, the ECM disables the
starter relay until the fault is corrected..
3.3 Diagnostic Trouble Codes
Each diagnostic trouble code is diagnosed by following a specific testing procedure. The
diagnostic 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 diagnostic trouble codes using the DRB. This procedure begins in
the DTC TEST - Checking the System for Diagnostic Trouble Codes. This will direct you to the
specific test(s) that must be performed.
3.3.1 Hard Code
A diagnostic trouble code that comes back within one cycle of the ignition key is a ªhardº code.
This means that the defect is there every time the engine control module/SKIM 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 ªintermittentº test must be performed.
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3.3.2 Intermittent Code
A diagnostic trouble code that is not there every time the engine control module/SKIM checks the
circuit is an ªintermittentº code. Most intermittent codes are caused by wiring or connector
problems. Defects 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 checks may assist you in
identifying a possible intermittent problem:
²Visually inspect related wire harness connectors. Look for broken, bent, pushed out, or
corroded terminals.
²Visually inspect the related harnesses. Look for chafed, pierced, or partially broken wire.
²Refer to any hotlines or technical service bulletins that may apply.
NOTE: Electromagnetic (radio) interference can cause an intermittent system malfunction. This
interference can interrupt communication between the ignition key transponder and the SKIM.
3.3.3 Reset Counter
The reset counter counts the number of times the vehicle has been started since codes were last
set, erased, or the battery was disconnected. The reset 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 ECM and can be viewed on the DRB as the RESET COUNTER.
When there are no trouble codes stored in memory, the DRB will display ªNO TROUBLE CODES
FOUNDº and the reset counter will show ªRESET COUNT = XXX.º
3.3.4 ECM Diagnostic Trouble Codes
A/C CONTROL SHORT CIRCUIT
A/C CONTROL OPEN CIRCUIT
A/C SYSTEM PRESSURE SIGNAL HIGH EXCEEDED
A/C SYSTEM PRESSURE SIGNAL LOW EXCEEDED
A/C SYSTEM PRESSURE SUPPLY HIGH EXCEEDED
A/C SYSTEM PRESSURE SUPPLY LOW EXCEEDED
ACCELERATOR PEDAL SENSOR SIGNAL HIGH EXCEEDED
ACCELERATOR PEDAL SENSOR PLAUSIBILITY
ACCELERATOR PEDAL SENSOR PWG PLAUS WITH LOW IDLE SWITCH
ACCELERATOR PEDAL SENSOR PWG PLAUS WITH POTENTIOMETER
ATMOSPHERIC PRESSURE SENSOR SRC HIGH EXCEEDED
ATMOSPHERIC PRESSURE SENSOR SRC LOW EXCEEDED
BATTERY VOLTAGE SRC HIGH EXCEEDED
BRAKE SIGNAL PLAUS WITH REDUNDANT CONTACT
CLUTCH SIGNAL PLAUSIBILITY
CONTROL SLEEVE SENSOR SIGNAL HIGH EXCEEDED
CONTROL SLEEVE SENSOR START END POS. NOT ATTAINED
CONTROL SLEEVE SENSOR STOP END POS. NOT ATTAINED
CRUISE STATUS INDICATOR LAMP SHORT CIRCUIT
DIAGNOSTIC LAMP OPEN CIRCUIT
DIAGNOSTIC LAMP SHORT CIRCUIT
DIESEL POWER RELAY SHUTS OFF TOO EARLY
DIESEL POWER RELAY SHUTS OFF TOO LATE
EEPROM PLAUSIBILITY CHECKSUM ERROR FOR ADJ. (EGR)
EEPROM PLAUSIBILITY CHECKSUM ERROR IN CC212
EEPROM PLAUSIBILITY COMMUNICATION WITH EEPROM
EEPROM PLAUSIBILITY FUNC. SWITCH WRONG OR MISSING
EEPROM PLAUSIBILITY VER. NUMBER NOT CORRESPONDING
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EGR OPEN CIRCUIT
EGR SHORT CIRCUIT
ENGINE SPEED SENSOR DYNAMIC PLAUSIBILITY
ENGINE SPEED SENSOR OVER SPEED RECOGNITION
ENGINE SPEED SENSOR STATIC PLAUSIBILITY
FAN CONTROL OPEN CIRCUIT FAN#1
FAN CONTROL OPEN CIRCUIT FAN #2
FAN CONTROL SHORT CIRCUIT FAN #1
FAN CONTROL SHORT CIRCUIT FAN #2
FUEL QUANTITY ACTUATOR NEG. GOV. DEVIATION COLD
FUEL QUANTITY ACTUATOR NEG. GOV. DEVIATION WARM
FUEL QUANTITY ACTUATOR POS. GOV. DEVIATION COLD
FUEL QUANTITY ACTUATOR POS. GOV. DEVIATION WARM
FUEL TEMPERATURE SENSOR SRC HIGH EXCEEDED
FUEL TEMPERATURE SENSOR SRC LOW EXCEEDED
GLOW RELAY #1 CONTROLLER OPEN CIRCUIT
GLOW RELAY #2 CONTROLLER OPEN CIRCUIT
GLOW RELAY #1 CONTROLLER SHORT CIRCUIT
GLOW RELAY #2 CONTROLLER SHORT CIRCUIT
IMMOBILIZER SIGNAL LOST
INVALID SKIM MESSAGE
INDUCTIVE AUX. SPEED SENSOR DYNAMIC PLAUSIBILITY
INDUCTIVE AUX. SPEED SENSOR OVERSPEED RECOGNITION
INDUCTIVE AUX. SPEED SENSOR PLAUSIBILITY
INDUCTIVE AUX. SPEED SENSOR STATIC PLAUSIBILITY
MICROCONTROLLER GATE-ARRAY MONITORING
MICROCONTROLLER GATE-ARRAY WATCHDOG
MICROCONTROLLER PREPARE FUEL QUANTITY STOP
MICROCONTROLLER RECOVERY HAS OCCURRED
MICROCONTROLLER REDUNDANT OVERRUN MONITORING
NEEDLE MOVEMENT SENSOR SRC HIGH EXCEEDED
NEEDLE MOVEMENT SENSOR SRC LOW EXCEEDED
REDUNDANT EMER. STOP PLAUSIBILITY IN AFTER-RUN
REDUNDANT EMER. STOP POWERSTAGE DEFECTIVE
REGULATOR LOWER REGULATOR LIMIT
REGULATOR UPPER LIMIT
SOLENOID VALVE CONTROLLER OPEN CIRCUIT
SOLENOID VALVE CONTROLLER SHORT CIRCUIT
TEMPERATURE OF ENGINE COOLANT SRC HIGH EXCEEDED
TEMPERATURE OF ENGINE COOLANT SRC LOW EXCEEDED
TERMINAL #15 PLAUSIBILITY AFTER START-UP
TIMING GOVERNING NEGATIVE GOVERNOR DEVIATION
TIMING GOVERNING POSITIVE GOVERNOR DEVIATION
TURBOCHARGER BOOST SENSOR SIGNAL HIGH EXCEEDED
TURBOCHARGER BOOST SENSOR SIGNAL LOW EXCEEDED
TURBOCHARGER BOOST SENSOR SUPPLY HIGH EXCEEDED
TURBOCHARGER BOOST SENSOR SUPPLY LOW EXCEEDED
TURBOCHARGER BOOST SENSOR PLAUSIBILITY
VEHICLE SPEED SENSOR PEC FREQUENCY TOO HIGH
VEHICLE SPEED SENSOR SIGNAL SRC HIGH EXCEEDED
VEHICLE SPEED SENSOR PLAUSIBILITYG
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3.3.5 SKIM Diagnostic Trouble Codes
ANTENNA FAILURE
COP FAILURE
EEPROM FAILURE
PCM STATUS FAILURE
INTERNAL FAULT
RAM FAILURE
ROLLING CODE FAILURE
SERIAL LINK EXTERNAL FAULT
STACK OVERFLOW FAILURE
TRANSPONDER COMMUNICATION FAILURE
TRANSPONDER CRC (CYCLIC REDUNDANCY CHECK) FAILURE
TRANSPONDER ID MISMATCH
TRANSPONDER RESPONSE MISMATCH
VIN MISMATCH
3.3.6 Handling No Trouble Code Problems
After reading Section 3.0 (System Description and Functional Operation), you should have a
better understanding of the theory and operation of the on-board diagnostics, and how this relates
to the diagnosis of a vehicle that may have a driveability-related symptom or complaint.
The ``no code'' system is broken down into three test methods:
± No Code Complete Test
± No Code Quick Individual Test
± No Code Quick Symptom Test
3.4 Using the DRB
Refer to the DRB user's guide for instructions and assistance with reading trouble codes, erasing
trouble codes, and other DRB functions.
3.5 DRB Error Messages and Blank Screen
Under normal operation, the DRB will display one of only two error messages:
± ± User-Requested WARM Boot or User-Requested COLD Boot
This is a sample of such an error message display:
ver: 2.14
date: 26 Jul93
file: key_itf.cc
date: Jul 26 1993
line 548
err: 0x1
User-Requested COLD Boot
Press MORE to switch between this display
and the application screen.
Press F4 when done noting information.
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3.5.1 DRB Does Not Power Up
If the LED's do not light or no sound is emitted at start up, check for loose cable connections or
a bad cable. Check the vehicle battery voltage (data link connector cavity 16). A minimum of 11
volts at DLC cavity 16 is required to adequately power the DRB. Check for proper ground
connection at DLC cavities 4 and 5.
If all connections are proper between the DRB and the vehicle or other devices, and the vehicle
battery is fully charged, an inoperative DRB may be the result of faulty cable or vehicle wiring. For
a blank screen, refer to the appropriate diagnostics manual.
3.5.2 Display is Not Visible
Low temperatures will affect the visibility of the display. Adjust the contrast to compensate for this
condition.
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4.0 SYSTEM COMPONENT LOCATIONS
4.1 Engine Control Module
2.5L
CAV CKT/COLOR FUNCTION
1 Z12 BK/TN Ground
2 A142 DG/OR Diesel Power Relay Output
3 K90 TN Starter Relay Control
5 C13 DB/OR A/C Compressor Clutch Control
6 K159 VT/RD Engine Speed Sensor Signal
Output
8 C103 DG/LB A/C Switch Signal
9 K29 WT/PK Secondary Brake Switch Signal
11 K6 VT/WT 5-Volt Supply
12 K151 WT Low Idle Position Switch Sense
13 K21 BK/RD Intake Air Temperature Sensor
Signal
17 C24 DB/PK Low Speed Fan Control
20 L50 WT/TN Primary Brake Switch Signal
23 K167 BR/YL Accelerator Pedal Position
Sensor Ground
24 K22 OR/DB Accelerator Pedal Position
Sensor Signal
27 Z12 BK/TN Ground
28 A142 DG/OR Diesel Power Relay Output
29 K35 GY/YL EGR Solenoid Control
30 V38 LB/RD Speed Control Lamp Control
33 K51 DB/YL Diesel Power Relay Control
34 G85 OR/BK Diagnostic/Glow Plug Lamp
Control
38 G56 OR/BK Immobilizer Signal
39 K9 LB 5-Volt Supply
40 K1 DG/RD Boost Pressure Sensor Signal
41 C137 YL High Speed Fan ControlCAV CKT/COLOR FUNCTION
42 K152 WT/DG Glow Plug Relay #1 Control
43 K252 LG/OR Glow Plug Relay #2 Control
45 D21 PK ISO K-line
46 K119 LG/BK Clutch Pedal Switch Signal
47 F87 WT/BK Ignition Switch Supply
50 K7 OR 5-Volt Supply
51 G7 WT/OR Vehicle Speed Sensor Signal
52 C18 DB A/C Pressure Sensor Signal
53 K156 GY Fuel Temperature Sensor Signal
54 K2 TN/BK Engine Coolant Temperature
Sensor Signal
55 K68 LG/YL Needle Movement Sensor
Ground
56 K134 LB/BK Control Sleeve Position Sensor
Signal
57 K57 LG/OR Middle Tap
58 K135 WT/BK Measure Coil
59 K140 TN/WT Fuel Quantity Actuator Control
60 V37 RD/LG Speed Control Switch Signal
61 K4 BK/LB Sensor Ground
62 K67 BR/BL Needle Movement Sensor
Signal
66 K140 TN/WT Fuel Quantity Actuator Control
67 K24 GY/BK Engine Speed Sensor Signal
69 K3 BK/VT Engine Speed Sensor Ground
77 K153 OR/DG Fuel Shutdown Solenoid Control
79 K126 LG Fuel Timing Solenoid Control
80 K140 TN/WT Fuel Quantity Actuator Control
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4.2 Controls and Solenoids
4.3 Data Link Connector
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