14 volt battery? What do you mean by a 14 volt battery - never heard of one.

 

They make 12V, 14V, 16V, 19V and I think thats all for automotive use.
I'm using a XS Power D1400.

On the down side no luck with the PCM short to cover idea.
Going to pick one up tonight hopefully.

 

Of course it's up to you, but before installing the replacement PCM, I recommend you revert your battry back to a 12 volt battery (group 34/700 cranking amps) and reset your voltage regulator back to the voltage I previously stated. The elctonic and electrical systems in your Jeep were designed to operate on 12 volts, not 14.

The battery temperature sensor is required in a normal charging system and may still play an important roll with your aftermarket voltage regulator system. So-install a new battery temp sensor or repair the wiring to your existing one. You can check the battery temp sensor with an Ohmmeter set at 20K Ohms. Touch the two wire pin sockets of the sensor connector with the meter probes. At 75-80*F, an Ohmmeter reading of 9,000 (9K) to 11,000 (11K) Ohms should be observed.

I think you mentioned that your crankshaft position sensor wiring was damaged as well. Try repairing this wiring or replace the CPS.

If nothing else, turn down the voltage adjustment on your aftermarket voltage regulator before replacing the PCM.

Good luck.

 

I got a new PCM installed, but I am wondering do I have to get it programmed to start the car?
I left the battery temp sensor unplugged, and yea the CrankPS is new already.

It is installed, and shows NO KEY signal on the upper left corner.
As usual it cranks and does not start.

 

checked all compression for the hell of it
150psi on all 6 cylinders! 175K not bad.
Especially on a cold motor that has been sitting in a cold garage for about 2 weeks.


Still no spark, ignition switch? Is there a coil driver somewhere?
Please help me out I am so stuck on this and even had to turn down a couple of job offers because I have no car currently

 

Well once again I made 100% sure #1 was at TDC on compression stroke.
This is proving to be a royal pain in the ***!

Still no spark
Can someone please point out what I am missing?

 

Answer these questions and get back.

 

Yes sir!
Let me add to that, I did make sure the model numbers were the exact same on the PCM.
Only difference I could clearly see was it came from a 2 door cherokee.

Is this "NO KEY" light a circle with an image of a key in it with a diagonal line through it? If so, that's a Sentry Key Immobilizer light.
Yea thats it.

1. Do you have a Sentry Key Immobilizer system in your Jeep?
I honestly have no idea. But I would assume so, because I have the newer style grey key. (2000 model)

2. Have you EVER seen this "NO KEY" light before having your starting problem, or before installing the new PCM?
No, I have never even noticed there was a light on the dash for the immobilizer before trying with this PCM.

3. Does this "NO KEY" light come on and stay on steady when you turn the key to RUN or START, or does it flash at all?
No, it goes on as all the gauges do their "check function" at key on. Turns off then comes right back on and it will stay solid then.

If you don't have a Sentry Key Immobilizer system, the new PCM you installed may be programmed for the Sentry Key Immobilizer system and is preventing the engine from starting.
This would make sense, but at this point I am wondering if I should try to get it reprogrammed first? Trying to pinpoint the suspect without $, but I do understand certin things need to be done in order to do that.

If you do have a Sentry Key Immobilizer system the Sentry Key Immobilizer Module (SKIM) or the Sentry Key (ignition key) may be defective, preventing the engine from starting.
This would make the most sense out of anything to me, But I guess the issue now would be identifying if I have it?
I will google now and look for ways to identify

 

Well after 5 minutes of searching, I feel like an idiot.

The brain of the immobilizer is located behing the glove box somewhere?
I will try to find that and make sure all connections are tight.

And then of course, since I have changed the PCM
I have to bring it to the dealer for reprogramming?
Hoping I can use my current keys.

But my real question is, was it the PCM or the immobilizer that failed?
If I bring it to the dealer with an immobilizer problem I know where thats gonna go-
$$ out of the behind.

What would the immobilizer limit? Spark alone?
I ask because if it was the immobilizer, I would think it uses the ASD?

 

Also is it true that it should at least turn over even if the immobilizer is the issue?

My friend had a 2004 Grand Cherokee 4.7
No sentry keys fit the ignition switch but he was able to start the car and it would run for a good minute before it died
beause of the immobilizer.

And if he held the key to the ignition switch long enough, it would run as normal and he would drive this thing everywhere no problems?

 

Here's a few images of the SKIS components. Note the shape of the Sentry Key. I think it is Gray.

The SKIM is on the steering column/ignition switch, not behind the gloove box.





Don't get too far ahead of yourself. Your PCM may not need any programming, and there may be nothing wrong with it. And forget about how the system works in different vehicles.

Stay with determining if you do have a SKIS. Does your key look like the one in the pic? You can pop the lid off the key and see if there's a transponder in it. If there is, you have been kissed by the SKIS witch.

The SKIM is powered from fuse #27 in the PDC (Battery Bus), and from fuse #9 in the JB (Start-Run Bus) through the ignition switch.

I'll post some text pertaining to the SKIS so that you will understand how it works, but in the mean time you can check those fuses and see if you can look inside your ingintion key.

The following is a brief about the Immobilizer lamp. I'll post the rest later.

INDICATOR LAMP

The Sentry Key Immobilizer System (SKIS) indicator
lamp gives an indication when the SKIS is faulty
or when the vehicle has been immobilized due to the
use of an invalid ignition key. The lamp is controlled
by the instrument cluster circuitry based upon messages
received from the Sentry Key Immobilizer
Module (SKIM) on the Chrysler Collision Detection
(CCD) data bus.
The SKIM sends messages to the instrument cluster
to turn the lamp on for about three seconds when
the ignition switch is turned to the On position as a
bulb test. After completion of the bulb test, the SKIM
sends bus messages to keep the lamp off for a duration
of about one second. Then the SKIM sends messages
to the instrument cluster circuitry to turn the
lamp on or off based upon the results of the SKIS
self-tests. If the SKIS indicator lamp comes on and
stays on after the bulb test, it indicates that the
SKIM has detected a system malfunction and/or that
the SKIS has become inoperative.
If the SKIM detects an invalid key when the ignition
switch is turned to the On position, it sends messages to

the instrument cluster to flash the SKIS indicator lamp.

 

A lot of good information for the future!

Starting at step 1,
Seems like the key does not contain a cavity.
I attempted to pry it apart with a small flathead at the middle section of the grey area, where the two halfs come together.

And it seems to be malleable rubber, and did not pop off as you decribed.
So I would assume I do not have SKIS?

 

I myself have never disassmbled the Sentry Key so I'm not sure this is a conclusive test.

You may want to try and access the SKIM location (see pic above) and see if it's there. There are three screws holding the lower shroud to the upper shroud around the ignition switch. Try and get the lower shroud off and see if the SKIM is there. Let me know what you find.

 

Here's some reading about the SKIS:

SENTRY KEY IMMOBILIZER SYSTEM

The Sentry Key Immobilizer System (SKIS) is designed to provide passive protection against unauthorized vehicle use by preventing the engine from operating while the system is armed. The primary components of this system are the Sentry Key Immobilizer Module (SKIM), the Sentry Key transponder, the SKIS indicator lamp, and the Powertrain Control
Module (PCM). The SKIM is installed on the steering column near the ignition lock cylinder. The transponder is located under the molded rubber cap on the head of the ignition
key. The SKIS indicator lamp is located in the instrument cluster.

The SKIS includes two valid Sentry Key transponders from the factory. If the customer wishes, additional non-coded blank Sentry Keys are available. These blank keys can be cut to match a valid ignition key, but the engine will not start unless the key transponder is also programmed to the vehicle using the Customer Learn programming procedure or a DRBIII scan tool. The
SKIS will recognize no more than eight valid Sentry Key transponders at any one time.

The SKIS performs a self-test each time the ignition switch is turned to the On position, and will
store Diagnostic Trouble Codes (DTCs) if a system malfunction is detected. The SKIS can be diagnosed, and any stored DTC can be retrieved using a DRBIII scan tool as described in the proper Diagnostic Procedures manual.

DESCRIPTION AND OPERATION

SENTRY KEY IMMOBILIZER MODULE

The Sentry Key Immobilizer Module (SKIM) contains a Radio Frequency (RF) transceiver and a central processing unit, which includes the Sentry Key Immobilizer System (SKIS) program logic.

The SKIS programming enables the SKIM to program and retain in memory the codes of at least one, but no more than eight electronically coded Sentry Key transponders. The SKIS programming also enables the SKIM to communicate over the Chrysler Collision Detection (CCD) data bus network with the Powertrain Control Module (PCM), the instrument cluster and/or the DRBIII scan tool.

The SKIM transmits and receives RF signals through a tuned antenna enclosed within a molded plastic ring formation that is integral to the SKIM housing. When the SKIM is properly installed on the steering column, the antenna ring is oriented around the circumference of the ignition lock cylinder housing. This antenna ring must be located within eight millimeters (0.31 inches) of the Sentry Key in order to ensure proper RF communication between the SKIM and the Sentry Key transponder. For added system security, each SKIM is programmed with a unique “Secret Key” code and a security code (PIN). The SKIM keeps the “Secret Key” code in memory. This “Secret Key” code must be transferred to the PCM memory during the initialization/ programming of the SKIS when the vehicle is manufactured, and each time the PCM is replaced during vehicle service by the dealer technician. The SKIM also transfers the “Secret Key” code to the memory of each of the Sentry Key transponders during new key programming. The security code is used by the assembly plant to access the SKIS for initialization, or by the dealer technician to access the system for service. The SKIM also stores in its memory the Vehicle Identification Number (VIN), which it learns through a CCD data bus message from the PCM during initialization.

The SKIM and the PCM both use software that includes a rolling code algorithm strategy, which
helps to reduce the possibility of unauthorized SKIS disarming. The rolling code algorithm ensures security by preventing an override of the SKIS through the unauthorized substitution of the SKIM or the PCM. However, the use of this strategy also means that replacement of either the SKIM or the PCM units will require a system initialization procedure to restore system operation.

 

So based on this read, What I think I understand is-
The key should react the same way as my friends GC (sorry to keep bringing it up but it fits the bill pretty well)
With the radio freq going to the key and back.

Also my key, being from a different PCM
Will need to be synched with this new PCM?

I am wondering why the light is solid and not flashing as previously described?

Here is a pic to confirm what I think looks like the SKIM.
(blurry camera sorry did the best I could)