Jeep Wrangler Forum - Reply to Topic
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > JK Jeep Wrangler Forum > JK General Discussion Forum > PCM fix .... negative!

Join Wrangler Forum Today


Thread: PCM fix .... negative! Reply to Thread
Title:
  
Message:
Post Icons
You may choose an icon for your message from the following list:
 

Register Now

In order to be able to post messages on the Jeep Wrangler Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Additional Options
Miscellaneous Options

Topic Review (Newest First)
05-29-2012 04:20 PM
GonzoBobH Taking this info to the shop...
12-14-2011 03:45 PM
willee51
Quote:
Originally Posted by xsdbs View Post
They hard wire it to a clean metal surface area to have the least resistance in the circuit. Having a ground tied to other grounds can cause resistance issues as well as other issues. Not to mention that a ground can be overloaded if it is a smaller gauge wire and has to many circuits on it. So the vehicle is broken down into sections with grounds in several areas to keep the ground wire run short as possible. The longer the wire, the more resistance in the wire so the ground is not good.
Some modules are also high current modules and need a larger wire than what would be desired to run thru a long body harness, causing the harness to be rather stiff. With grounds, the shorter the better, a ground that is over 13 inches long can also become an antennae picking up interference which may be undesirable to the module.
------------------

I have learned something now. Thanks
12-14-2011 08:20 AM
xsdbs They hard wire it to a clean metal surface area to have the least resistance in the circuit. Having a ground tied to other grounds can cause resistance issues as well as other issues. Not to mention that a ground can be overloaded if it is a smaller gauge wire and has to many circuits on it. So the vehicle is broken down into sections with grounds in several areas to keep the ground wire run short as possible. The longer the wire, the more resistance in the wire so the ground is not good.
Some modules are also high current modules and need a larger wire than what would be desired to run thru a long body harness, causing the harness to be rather stiff. With grounds, the shorter the better, a ground that is over 13 inches long can also become an antennae picking up interference which may be undesirable to the module.



Quote:
Originally Posted by kbwwolf View Post
Was that part of the sPOD advice you gave me a few weeks ago?
12-13-2011 03:07 PM
willee51
Oh, yes!

Quote:
Originally Posted by Vin View Post
Yes, it's crazy what a stupid ground wire can do, especially with these computers. I'd love to throw a V8 in with a carburator (or 3) and skip the computer all together.
---------
X2
12-12-2011 10:15 PM
kbwwolf Man, I'd buy that Jeep.
12-12-2011 09:55 PM
Vin
Quote:
Originally Posted by kbwwolf View Post
Was that part of the sPOD advice you gave me a few weeks ago?
Yes, it's crazy what a stupid ground wire can do, especially with these computers. I'd love to throw a V8 in with a carburator (or 3) and skip the computer all together.
12-12-2011 08:29 PM
kbwwolf
Quote:
Originally Posted by Vin View Post
That's crazy, I spent a month trying to figure out what was causing my ESP BAS ABS and traction control lights to stay on. It was 2 weeks after I put on my lift. I must retorqued the suspension parts at least 3 times and checked the steering wheel 10 times. It turned out being a ground wire for the ECU/PCM not making a good contact with the module. You'd thing they'd hard wire the ground to the PCM instead of connecting it to one of the mounting screws.

In either case. I'm gkad you are back in the game.
Was that part of the sPOD advice you gave me a few weeks ago?
12-12-2011 08:20 PM
Vin That's crazy, I spent a month trying to figure out what was causing my ESP BAS ABS and traction control lights to stay on. It was 2 weeks after I put on my lift. I must retorqued the suspension parts at least 3 times and checked the steering wheel 10 times. It turned out being a ground wire for the ECU/PCM not making a good contact with the module. You'd thing they'd hard wire the ground to the PCM instead of connecting it to one of the mounting screws.

In either case. I'm gkad you are back in the game.
12-12-2011 05:42 PM
jmb6420 Glad to hear it. There's nothing worse than a new toy you can't play with!
12-12-2011 05:19 PM
willee51
Still ging strong..........

Three days, since out of the shop and still running STRONG

Damn, I LOVE driving this thing
12-11-2011 09:01 AM
basecamper
Quote:
Originally Posted by willee51 View Post
------------------------------------------------------
...Being back in my 2012 JKU is as good as REAL sex

------------------------------------------
Really!

On another note I'm glad its fixed and it's also nice that they were able to isolate the problem so that you feel more comfortable in the Jeep vs the phantom problem that just fixes itself.
12-11-2011 07:23 AM
CLOTAGAMES Electrical issues are one of the hardest to find-Glad they got it fixed. Factory wiring diagrams are usually pretty poor.
12-10-2011 06:39 PM
xsdbs Can you get a picture of the ground location?



Quote:
Originally Posted by willee51 View Post
------------------------------------------------------
Picked her up this AM and been in her all day running errands!

They even showed me the location of the ground fault.

The notes from my 2nd visit:

“Diagnosed and found damaged coil and checked for shorts. None found. Found voltage and ohms are the same as other cylinders.. Replaced PCM & Test Drove. Coil popped again????? Instructed to hard-wire coil per “STAR” & replace coil. Found Map Sensor, TPS, & ETC ……. Lost Grounds. Found wires grounding against AC Line, repaired and insulated wiring over AC line.”

So far she is running like a top!

Being back in my 2012 JKU is as good as REAL sex

------------------------------------------
12-10-2011 06:11 PM
TroutSafari Christmas Food Court Flash Mob, Hallelujah Chorus - Must See! - YouTube
12-10-2011 03:51 PM
FOUR FLUSHER Great news!!!!
12-10-2011 03:22 PM
willee51
Shop notes for you folks...

Quote:
Originally Posted by Yozho View Post
Damn! I was just going to post to check your grounds. I used to be in a VW club and some of them were notorious for gremlin-type, WTF NOW, issues. Issues that just had no rhyme or reason.

But damned if the gremlins weren't banished each time when the ground connections, ALL OF THEM, were inspected and cleaned if necessary.

Unfortunately, I have no idea where they all are on a JK yet.

I sure hope this is the resolution for you!!
------------------------------------------------------
Picked her up this AM and been in her all day running errands!

They even showed me the location of the ground fault.

The notes from my 2nd visit:

“Diagnosed and found damaged coil and checked for shorts. None found. Found voltage and ohms are the same as other cylinders.. Replaced PCM & Test Drove. Coil popped again????? Instructed to hard-wire coil per “STAR” & replace coil. Found Map Sensor, TPS, & ETC ……. Lost Grounds. Found wires grounding against AC Line, repaired and insulated wiring over AC line.”

So far she is running like a top!

Being back in my 2012 JKU is as good as REAL sex

------------------------------------------
12-10-2011 05:08 AM
Yozho
Quote:
Originally Posted by willee51 View Post

It was a ground-wire, making contact with whatever?
Damn! I was just going to post to check your grounds. I used to be in a VW club and some of them were notorious for gremlin-type, WTF NOW, issues. Issues that just had no rhyme or reason.

But damned if the gremlins weren't banished each time when the ground connections, ALL OF THEM, were inspected and cleaned if necessary.

Unfortunately, I have no idea where they all are on a JK yet.

I sure hope this is the resolution for you!!
12-09-2011 11:31 PM
CG3 Hallefreakinglujah!
12-09-2011 11:24 PM
AntiTrust this is why my power probe is worth more then its weight in gold
12-09-2011 11:13 PM
Up Hill Bill Great news, Willee.

Now, get out on (or off) the road and enjoy our new Jeep!
12-09-2011 10:00 PM
fawsty I think I would take the seat covers, and any other add-ons with me to the dealership, and tell them to install them, seeing that you couldn't in this whole process.....Just don't make them put the lift on it.
12-09-2011 06:19 PM
JIMBOX Told ya, I had the faith Willee--

Situation --RESOLVED--

JIMBO
12-09-2011 06:00 PM
kjeeper10 Yaaaayyyyyyyyy


Yes I screamed out load.
12-09-2011 05:46 PM
LaTuFu Glad to hear that it was resolved.
12-09-2011 05:43 PM
JEEPDON Yes; Electrical problems can amount to chasing ghosts!!
I am glad for you that they were able to find it. Sometimes it has to be a major short before it can be located. Also Kudo's to the servicing dealer for putting in the effort to find it. Hope the best for you. And good luck on your upcoming retirement!!
Don
12-09-2011 05:27 PM
panthermark That is good news!
Holy cow....that must have taken a long ass time to trace....

Electrical gremlins suck....
12-09-2011 05:05 PM
joe002
Quote:
Originally Posted by willee51 View Post
...It was a ground-wire, making contact with whatever?

They separated the two, it then started (believe it or not) and they drove it over 20-mi, no problems...
When you pick it up maybe they can point out where the problem was? Hope they fixed it for you!
12-09-2011 05:04 PM
flyinion Congrats!! Wow sounds like you just got the random bad piece of wiring. It could happen to anything. Could have just been a small nick in the insulation that wasn't caught in QC when they built the harness and then it just happened to make contact with something due to its location. At least they found it
12-09-2011 05:01 PM
cosmos I hope it really is all fixed and this just becomes a funny story from way back when you first got the jeep
12-09-2011 04:50 PM
willee51
Think it's fixed.......

Got a call at 5:30pm this afternoon, from the Jeep Service Shop, saying my Jeep is fixed?????? Took the poor guys almost 2-weeks to locate this hidden demon and yes, they were doing their BEST?

It was a ground-wire, making contact with whatever?

They separated the two, it then started (believe it or not) and they drove it over 20-mi, no problems.

How the HELL can something so SIMPLE, cause so MUCH trouble and be so damn hard to find? Miles of wiring, covered, shielded and in extremely difficult to get to

Again, this seems to be limited to only my unit as far as I can find out.

Words cannot describe how much I want to get back in my JEEP

Thanks for the kindness and support shown me during this stresssful time

Now, I can install my new "seat-covers" that came while she was in the shop.
This thread has more than 30 replies. Click here to review the whole thread.

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT -5. The time now is 02:39 AM.



Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC