light CHRYSLER CARAVAN 2000 Service Manual

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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3.5.1 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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TEST TC-76AREPAIRING - SMART START RELAY SHORT CIRCUIT
Perform TEST DTC Before Proceeding
*Perform Verification TEST VER-1A. **Check connectors - Clean / repair as necessary.
REPLACE THE
START TEST STARTER RELAY WITH
TC-76A. A KNOWN GOOD
RELAY.
FIG.1
FULLY DEPRESS THE
CLUTCH PEDAL AND DOES THE ENGINE YES REPLACE THE
ATTEMPT TO CRANK CRANK? INITIAL STARTER
THE ENGINE RELAY.
NO
KEY OFF.
REMOVE THE STARTER REMOVE THE DIESEL
DISCONNECT THE ECM RELAY.** POWER RELAY.**
HARNESS
CONNECTORS.**
WITH A JUMPER WIRE, KEY ON. USING A REPAIR THE STARTER
CONNECT DIESEL POWER TEST LIGHT, PROBE IS THE TEST LIGHT YES RELAY CONTROL
RELAY CONN. CAVITIES THE STARTER RELAY ON? CIRCUIT FOR A
30 AND 87 (IN PDC). CONTROL CIRCUIT. SHORT TO VOLTAGE.*
FIG.1 FIG.1
NO
REPLACE THE ENGINE
CONTROL MODULE.*
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TEST NTC-2ACHECKING GLOW PLUG OPERATION
Perform TEST NTC-1A Before Proceeding
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
THE 2.5L DIESEL GLOW PLUG RELAY #1 GLOW PLUG RELAY #2
START TEST ENGINE UTILIZES SUPPLIES POWER TO SUPPLIES POWER TO
NTC-2A. TWO GLOW PLUG THE GLOW PLUGS IN THE GLOW PLUGS IN
RELAYS... CYLINDERS #1 & #4. CYLINDERS #2 & #3.
PERFORM THIS TEST
ON GLOW PLUG RELAY
#1 THEN REPEAT TURN IGNITION OFF.
TEST FOR GLOW PLUG
RELAY #2.
DISCONNECT EACH KEY ON. USING THE
GLOW PLUG HARNESS DRB, ACTUATE THE
CONNECTOR. GLOW PLUG RELAY.
USING A TEST
LIGHT, PROBE THE DOES THE TEST NO TEST NTC-2A
APPROPRIATE GLOW LIGHT FLASH ON AND CONTINUED ON
PLUG HARNESS CONN. OFF? THE NEXT PAGE.
FIG.1 AND 2
YES
GLOW PLUG CIRCUITRY
OK. REFER TO SERVICE
MANUAL TO CHECK GLOW TEST COMPLETE.*
PLUG OPERATION.
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TEST NTC-4ACHECKING THE PCM POWER AND GROUNDS
Perform TEST NTC-1A Before Proceeding
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
NOTE: THE BATTERY
START TEST MUST BE FULLY
NTC-4A. CHARGED TO PERFORM
THIS TEST.
TURN IGNITION OFF. WITH AN OHMMETER,
DISCONNECT THE ECM MEASURE ECM IS THE RESISTANCE NO REPAIR THE OPEN
HARNESS HARNESS CONNECTOR BELOW 5.0 OHMS FOR GROUND CIRCUIT.*
CONNECTORS.** CAVITIES 1 AND 27 ALL MEASUREMENTS?
TO GROUND. FIG.1
YES
PROBE DIESEL POWER
USE A TEST LIGHT RELAY CONNECTOR DOES THE TEST NO REPAIR OPEN
IN THE FOLLOWING CAVITY (PDC) 3(30). LIGHT ILLUMINATE BATTERY SUPPLY TO
STEPS. BRIGHTLY? RELAY.
FIG.2
YES
REMOVE THE DIESEL 3(30) AND 5(87). DOES THE TEST
POWER RELAY. CONNECT WITH A TEST LIGHT, LIGHT ILLUMINATE NO REPAIR OPEN DIESEL
A JUMPER WIRE ACROSS PROBE ECM HARNESS BRIGHTLY FOR EACH POWER RELAY OUTPUT
RELAY CONNECTOR CONNECTOR CAVITIES CAVITY? CIRCUIT.*
(PDC) CAVITIES... 2 AND 28. FIG.2
YES
WITH A TEST LIGHT,
PROBE ECM HARNESS DOES THE TEST NO REPAIR THE OPEN
TURN IGNITION ON. CONNECTOR CAVITY 47. LIGHT ILLUMINATE FUSED IGNITION
BRIGHTLY? SWITCH CIRCUIT.*
FIG.1
YES
ECM GROUND
AND POWER
CIRCUITS ARE
OK. TEST
PASSED.
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TEST NTC-10ACHECKING THE FUEL HEATER AND THE CRANKCASE VENT HEATER
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
TURN IGNITION OFF.
START TEST YES PERFORM TEST
NTC-10A. INSPECT FUSE #16 IS THE FUSE OPEN? NTC-10B.
IN THE PDC.
NO
USING A TEST
REMOVE THE FUEL LIGHT, PROBE RELAY IS THE TEST LIGHT NO REPLACE THE POWER
HEATER RELAY.** CONNECTOR CAVITY ON? DISTRIBUTION
30 (IN PDC). CENTER.*.
FIG. 1
YES
USING A TEST REPAIR THE FUSED
LIGHT, PROBE FUSED IS THE TEST LIGHT NO IGNITION SWITCH
TURN IGNITION ON. IGNITION SW OUTPUT ON? OUTPUT CIRCUIT FOR
CKT (IN PDC). AN OPEN OR SHORT
FIG. 1 TO GROUND.*
YES
WITH IGNITION RELAY CONNECTOR
STILL ON, CONNECT CAVITIES 85 AND 86 IS THE TEST LIGHT NO REPAIR THE OPEN
A TEST LIGHT (IN PDC). ON? RELAY GROUND
ACROSS...CIRCUIT.*
FIG. 1
YES
KEY OFF. DISCONNECT THE
FUEL HEATER AND CONTINUE TEST
INSTALL THE FUEL CRANKCASE VENT TURN IGNITION ON. NTC-10A ON THE
HEATER RELAY. HEATER HARNESS NEXT PAGE.
CONNECTORS.**
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TEST NTC-10ACONTINUED - CHECKING THE FUEL HEATER AND THE CRANKCASE VENT HEATER
*Perform Verification TEST VER-2A. **Check connectors - Clean / repair as necessary.
TEST NTC-10A CONNECT A TEST
CONTINUED FROM WITH THE IGNITION LIGHT BETWEEN
THE PREVIOUS STILL ON... GROUND AND THE
PAGE. FUEL HEATER RELAY
OUTPUT CKT. AT...
THE CRANKCASE VENT REPAIR THE OPEN FUEL
HEATER HARNESS IS THE TEST LIGHT NO HEATER RELAY OUTPUT
CONNECTOR. ON? CKT FROM THE SPLICE
TO THE CRANKCASE
FIG. 1 VENT HEATER.*
YES
CONNECT A TEST LIGHT REPAIR THE OPEN
ACROSS THE CRANKCASE IS THE TEST LIGHT NO CRANKCASE VENT
VENT HEATER HARNESS ON? HEATER GROUND
CONNECTOR. CIRCUIT.*
FIG. 1
YES
USING AN OHMMETER,
MEASURE RESISTANCE IS THE RESISTANCE NO REPLACE THE
OF THE CRANKCASE BETWEEN CRANKCASE VENT
VENT HEATER. 10.0 AND 16.0 OHMS? HEATER.*
FIG.1
YES
TEST COMPLETE.
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TEST NS-2BREPAIRING A NO RESPONSE CONDITION
Perform TEST NS-2A Before Proceeding
*Perform Verification TEST VER-1A. **Check connectors - Clean / repair as necessary.
WAS THE IGNITION TURN IGNITION ON
START TEST ON WHEN THE "NO NO TO GET A RESPONSE.
NS-2B. RESPONSE" MESSAGE
WAS DISPLAYED? TEST COMPLETE.
YES
KEY ON. PROBE THE
ISO K-LINE CIRCUIT IS THE TEST LIGHT YES REPAIR THE ISO
USE A TEST LIGHT AT THE DLC. ON? K-LINE FOR A SHORT
IN THE FOLLOWINGTO VOLTAGE.*
STEP. FIG.1
NO
KEY OFF.
DISCONNECT DRB
DISCONNECT THE ECM FROM THE DATA LINK
HARNESS CONNECTOR.
CONNECTORS.**
MEASURE THE
USE AN OHMMETER IN RESISTANCE OF THE IS THE RESISTANCE YES REPAIR THE ISO
THE FOLLOWING ISO K-LINE AT THE BELOW 5.0 OHMS? K-LINE CIRCUIT FOR
STEPS. DLC CONNECTOR TO A SHORT TO GROUND.
GROUND FIG.1
NO
MEASURE THE
RESISTANCE OF THE IS THE RESISTANCE NO REPAIR THE OPEN
ISO K-LINE AT THE BELOW 5.0 OHMS? ISO K-LINE
DLC CONN. TO THE CIRCUIT.
ECM CONN. FIG.2
YES
MEASURE BETWEEN THE DLC CAVITIES REPAIR THE GROUND
CHASSIS GROUND AND 4 AND 5. IS THE RESISTANCE NO CIRCUIT(S) THAT
THE GROUND BELOW 5.0 OHMS FOR MEASURED ABOVE 5.0
CIRCUITS AT... EACH MEASUREMENT? OHMS FOR AN OPEN.*
FIG.1
YES
CONTINUE TEST
NS-2B ON THE
NEXT PAGE.
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