Does the pcm or ecm have a skim module secret code, if a 2002 jeep wrangler did not have the theft module installed at the factory,If not how does the dealership get a code to program the Ign. immobil

Anti-theft system problem ! need to take to the dealer !

bypass as in HACK?
you cant,
old cars yes, but not newer.
by design. and law.
this IMMOblizer, (called by jeep. SKIM)

http://www.fixkick.com/Jeeps/SKIM.html

FSM


read the FSM book yet on 2002? chapter on SKIM.
http://www.jeep4x4center.com/knowledge-base/index.htm?utm_source=cj#service
chapter 8E, electronic modules.
page 21. read that page first . it answers why.
see secret key code and pin, good luck hacking that.


The skim module blocks the ASD relay (stalls engine)
scanning the PCM with any scan tool it will show, why.
SKIM key wrong, or ?
and with that error the ASD drops and the scan tool tells you that.
so, that means you need to make the SKIM happy.
hacking it , ill not cover, but good luck, its not easy and in most cases impossible.
and if you continue to hack away, the PCM sees that and bricks it self and other modules on the bus as punishments.

good luck hacking.

what does RESET mean, do say.?
the SKIM resets every time you turn ignition off.
why not (pray tell) post a symptom and not try to guess fixes.
?
car dont start
car starts runs for 2-3 seconds and dies.
what./
SKIM light glowing well , it will if SKIM is upset (Immoblizer )
the next steps are)
1: check all fuses.
2; and scan the PCM at the 16pin female jack a knees.
an innova 3160 is a nice tool own.
if lacking car repair tools why hot get car serviced.
if car will not move, call a tow. to any ASE shop.
the scan tool will tell you why engine will not start (if can crank)
it will.
this year car has EXTENSIVE PCM diagnostics, (lots of DTCs)
P1685 (6/7)? (skim key wrong)????

you can pull the SKIM fuse #7 and 22 (cab box, not PDC)
this kills PCM and skim. (no power)

you are swapping PCM's that be real bad.
on newer cars with Security this causes it to think your are a thief
and bricks the PCM (skim rules 101)
"until the pcm use in another jeep" huh?
SKIM is Phissed off.
http://www.jeepforum.com/forum/f9/trouble-code-p1686-905620/

great question, wana Read the shop manual for free, ?
it answers all this, its a rolling encrypted secret code.
bad idea
says it all, YOU DID.
now the system sees you hacking,
and bricks it.
there is only 1 fix. dealer time. or a shop with same tools.

they must be all married or they self brick
its also law here in use, DOT bs, rules.
not jeeps fault < GOV BS.

page 8e-1 , on, read. in jeep SM.

When a PCM (JTEC) and the SKIM are replaced
at the same time, perform the following steps in
order:
(1) Program the new PCM (JTEC).
(2) Program the new SKIM.
(3) Replace all ignition keys and program them to
the new SKIM.
PROGRAMMING THE PCM (JTEC)
The SKIS Secret Key is an ID code that is unique
to each SKIM. This code is programmed and stored
in the SKIM, the PCM, and the ignition key transponder
chip(s). When replacing the PCM, it is necessary
to program the secret key into the new PCM
using the DRBIIIt scan tool. Perform the following
steps to program the secret key into the PCM.
(1) Turn the ignition switch to the On position
(transmission in Park/Neutral).
(2) Use the DRBIIIt and select THEFT ALARM,
SKIM, then MISCELLANEOUS.
(3) Select PCM REPLACED (GAS ENGINE).
(4) Enter secured access mode by entering the
vehicle four-digit PIN.
(5) Select ENTER to update PCM VIN.
NOTE: If three attempts are made to enter secured
access mode using an incorrect PIN, secured
access mode will be locked out for one hour. To
exit this lockout mode, turn the ignition switch to
the ON position for one hour, then enter the correct
PIN. (Ensure all accessories are turned off. Also
monitor the battery state and connect a battery
charger if necessary).
(6) Press ENTER to transfer the secret key (the
SKIM will send the secret key to the PCM).

(7) Press PAGE BACK to get to the Select System
menu and select ENGINE, MISCELLANEOUS, and
SRI MEMORY CHECK.
(8) The DRBIIIt will ask, “Is odometer reading
between XX and XX?” Select the YES or NO button
on the DRBIIIt. If NO is selected, the DRBIIIt will
read, “Enter Odometer Reading (From I.P. odometer)”.
Enter the odometer reading from the instrument
cluster and press ENTER.
PROGRAMMING THE SKIM
(1) Turn the ignition switch to the On position
(transmission in Park/Neutral).
(2) Use the DRBIIIt and select THEFT ALARM,
SKIM, then MISCELLANEOUS.
(3) Select PCM REPLACED (GAS ENGINE).
(4) Program the vehicle four-digit PIN into SKIM.
(5) Select COUNTRY CODE and enter the correct
country.
NOTE: Be sure to enter the correct country code. If
the incorrect country code is programmed into
SKIM, it cannot be changed and the SKIM must be
replaced.
(6) Select YES to update VIN (the SKIM will learn
the VIN from the PCM).
(7) Press ENTER to transfer the secret key (the
PCM will send the secret key to the SKIM).
(8) Program ignition keys to the SKIM.
NOTE: If the PCM and the SKIM are replaced at the
same time, all vehicle ignition keys will need to be
replaced and programmed to the new SKIM.
PROGRAMMING IGNITION KEYS TO THE SKIM
(1) Turn the ignition switch to the On position
(transmission in Park/Neutral).
(2) Use the DRBIIIt and select THEFT ALARM,
SKIM, then MISCELLANEOUS.
(3) Select PROGRAM IGNITION KEY’S.
(4) Enter secured access mode by entering the
vehicle four-digit PIN.
NOTE: A maximum of eight keys can be learned to
each SKIM. Once a key is learned to a SKIM it (the
key) cannot be transferred to another vehicle.
(5) Obtain ignition keys to be programmed from
the customer (8 keys maximum).
(6) Using the DRBIIIt, erase all ignition keys by
selecting MISCELLANEOUS, and ERASE ALL CURRENT
IGN. KEYS.
(7) Program all of the ignition keys.
If ignition key programming is unsuccessful, the
DRBIIIt will display one of the following messages:
² Programming Not Attempted - The DRBIIIt
attempts to read the programmed key status and
there are no keys programmed into SKIM memory.
² Programming Key Failed (Possible Used
Key From Wrong Vehicle) - SKIM is unable to program
an ignition key transponder due to one of the
following:
² The ignition key transponder is faulty.
² The ignition key transponder is or has been
already programmed to another vehicle.
² 8 Keys Already Learned, Programming Not
Done - The SKIM transponder ID memory is full.
² Learned Key In Ignition - The ID for the ignition
key transponder currently in the ignition lock
cylinder is already programmed in SKIM memory.
end quote.

You do have a factory secuity system, and the used ignition lock is the problem, instyall the original lock into the used column.

DTC P0702 - Transmission Control System Electrical
There is a code in the ****** control module and need to check harnesses and wiring, as first step.

DTC P1685 - Skim Invalid Key
Transponder ID (in ignition key) is monitored with ignition on. DTC will set if transponder ID read by Smart Key Immobilizer Module (SKIM) does not match any transponder ID's stored in SKIM memory. Possible Causes:
- Incorrect VIN In PCM
- Invalid SKIM Key Present
- No Communication With SKIM
- No VIN Programmed In The PCM
- PCM SKIM Trouble Codes Set

I would suggest clearing all these codes, and drive it until the problem arises again, or the check engine light comes on, and then check for codes again. To clear the codes you will need to remove the negative battery cable, and touch it to the positive cable, for about 15 seconds. Then re hook and all the modules will be reset. If this isnt work, visit your Trans Service.

Hope this helps; also keep in mind that your feedback is important and I'll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using Fixya, and have a nice day.

CODE P1687 - NO CLUSTER BUS MESSAGE. POSSIBLE CAUSES DATA BUS CIRCUIT SKIM TO PCM IS DAMAGED OR ITS IS OPEN. PCM UNABLE TO COMMUNICATE WITH THE BODY CONTROL MODULE. PCM HAS FAILED OR THE SKIM IS DAMAGED OR HAS FAILED.

This is not an easy problem to solve at home for this vehicle. Far and away the most common cause of this issue is a faulty PCM (the vehicle's main computer). Did the vehicle just start dooing this all of a sudden with both keys? Or did it begin with one key not working and now neither works?
There are several potential causes, but in my experience it usually a bad PCM, bad SKIM (anti theft module) or the SKIM needs to be reprogrammed.
You are best advised to have it towed to the dealer or a reputable garage with experience in anti theft systems on Jeeps.

if you have sentry key on your jeep then it must be taken to a shop that can aacess the key code information to set up the vin and secret key into the pcm before it will stay running.. very few independant car repair shops can access that part of the controller... they will need a tool called the DRBIII .. its a dealer tool.. most dealers will set it up for about an hours shop labor but you will need the jeep towed in to them since it will not run...

but to acswer your question about how to change it its just a mater of disconnection the battery then unpluging the connectors from it and remove the bolts that hold it in place .. to install just rebolt it and then reconnect the connectors to it then reconnect the battery.. but with out skim set up it will not run... also not some dealers will tell you they cannot set up your vin and key info in the used contoller but it CAN be done...