Where do i find the pcm on my 2003 jeep liberty

There is no hard reset. You need a scan tool that is capable of programming a module. Call around to local shops or your closest dealer.

2002-2003 JEEP LIBERTY 3.7L RELUCTOR RING ... - eBay

https://www.ebay.com > itm
FOR SALE IS A 2002-2003 JEEP LIBERTY / 2002-2003 DODGE DAKOTA 3.7L V6 ENGINE 12 TEETH RELUCTOR RING. THIS ITEM IS ALSO KNOWS AS A TONE WHEEL. WILL FIT: 3.7L ...
Missing: 4x4 ‎' Must include: 4x4

2002-2003 jeep liberty 3.7 l reluctor ring 12 teeth tone ...

https://jeeppartsdepot.com > products > 2002-2003-jeep...
2002-2003 JEEP LIBERTY 3.7L RELUCTOR RING 12 TEETH TONE WHEEL CRANK SHAFT DODGE. Regular price: $129.00.
US$129.00 · ‎In stock
Missing: 4x4 ‎' Must include: 4x4

no idea to be honest earlier jeeps had then at the front of the wing down below as i remember ?? newer one would i imagine be in the electrical box under the bonnet near the battery

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/

Posted by Anonymous on Jan 25, 2013
why post to 2013? ELIAS? why not start your own post.
and not mix, engine sensors with HVAC blower heaters. hark.
the OP never once stated cars drive line.
and matters 100%
my guess is a jeep liberty with 3.7L and 2.4L 4 banger.
the answers vary by engines.
so if 161, is set the heater in bank 2 is bad, rear OXY sensor.
O2 Sensor Heater Circuit (Bank 2 Sensor 2)
the pcm measures the heater current flow
when it reads zero the sensor is bad or the wire is cut.(or rusty)

guess 2, is that late poster thinks
P0161 codes are HVAC codes
no it is not.
P0 codes are USA federal base codes.
and are for smog not dash HVAC heaters.
nice guess but dead wrong.

in most cases the 02 sensors is just bad.
the heater inside it just burns open.
all do that , every one... not one lasts
the life of engine, ever.

here ill read it to you, the SM. for 3.7L V6
gas engine, USA book and car....

Trouble Code: P0161 (3.7L V6 VIN K Auto)
O2 (B2 S2) Slow Response

Number of Trips to Set Code: 1

CCM Details

Trouble Code Conditions:
ECT Sensor less than 147?F and BTS signal within 27?F of the ECT Sensor (cold engine), engine started, system voltage over 10.5v, engine running at idle speed for over 12 seconds, and the PCM detected the O2 signal was more than 3.0v for 30-90 seconds.

Possible Causes:

ASD relay output (power) circuit to the heater is open

O2 heater ground circuit is open or O2 signal circuit open

O2 heater element has high resistance, is open or shorted

PCM has failed

2003 JEEP LIBERTY 2.4L 4-cyl Engine Code [
Engine Oil Grade 1....API* SAE 5W-30 is preferred.
CAPACITIES:
Engine, with filter..........4.7 liters

2003 JEEP LIBERTY 3.7L 6-cyl Engine Code

Engine Oil Grade 1......API* SAE 5W-30 is preferred.

CAPACITIES:
Engine, with filter..........4.7 liters

Thank you for using fixya and good luck

The ignition timing is off.
The ECM (Elctronic Control Module) is responsible for that.
Take the Liberty to AutoZone to have them scan the PCM code (free) and ask for an explanation print-out (also free). You might want them to clear the error code afterwards, too (yes, free).
Let us know what the codes are and a summary of the print-out.

Here are some things that I have run into. First any sensor cam/crank/tps etc..) that has a reference voltage from the pcm can cause this issue these sensors,(ESPECIALLY THE CRANK SENSORS or CAM Sensor) CAN SHORT OUT INTERNALLY. THIS WILL CAUSE A NO START CONDITION AND A "NO COMMUNICATION" ISSUE WITH THE PCM causing stalling. here are some things that I have run into. This condition has caused numerous unneeded pcm replacements. It gets difficult to diagnose when its an intermittent problem.sometimes a tech will install the pcm and let the jeep leave. Then when temp is right, the sensor shorts and it all happens again. Often by the time the jeep shows up on the hook the engine has cooled and the short is gone. In this case the tech has nothing to go on. YOU MOST LIKELY WONT HAVE A CODE HERE. THIS IS HOW I DIAGNOSE THE ISSUE. WHEN THE CONDITION IS PRESENT (NO COMMUNICATION") with THE KEY ON, START DISCONNECTING EACH SENSOR THAT HAS A REFERENCE VOLTAGE. START WITH THE CRANK SENSOR. IF YOU SEE THE SCANNER GET COMMUNICATION, THEN YOU FOUND THE SHORTED SENSOR.this CAN BE A PAIN IN THE @** IF THE CONDITION IS INTERMITTENT.
PLEASE NOTE: IT IS EXTREMELY RARE THAT THE PCM ITSELF HAS CAUSED THIS CONDITION. 99% OF THE TIME ITS A SENSOR SHORTING OUT, WIPING OUT ALL COMMUNICATION. ALSO NOTE:I HAVE NEVER SEEN THIS CONDITION ACTUALLY DAMAGE THE PCM. ONCE THE SHORTED SENSOR IS REPLACED, THE PCM IS FINE. THERE IS A RESISTOR IN THE PCM THAT PROTECTS IT FROM THIS. Good Luck and I Hope this will help resolve your issue. Please Rate Me. For any further assistance you can always ask me

2003 3.7 Liberty check engine light for crank....what? sensor? You have scanned it?

Hey, did you ever figure this out? Ever consider swapping PCM's for a newer 04 PCM that would be tuned for this engine?