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Unread 04-18-2013, 08:49 AM   #16
ZJNewbi3
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1995 ZJ 
 
Join Date: Mar 2013
Location: Milwaukee, Wisconsin
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The lights were going to go on the day it died Thanks for the connector! Trying to dig for that picture for weeks! I have a Haynes Manual and a download of a 1997 ZJ FSM that lists 4.0L, 5.2L, and diesel engines. Any place I can get a FSM for my 1995 ZJ 5.2L?
So far I'm going to check:

Grounds
o2 Sensor wires
PCM Connector (Pins: 3,6,7,11,12)

When I check the pins i should get:
12v on 3
5v on 6
8v on 7
and what on 11 and 12?

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Unread 04-18-2013, 12:48 PM   #17
ZeeJay1997
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Measure resistance from pin 11 and 12 to the negative battery post, not the terminal. Put meter on lowest ohm scale. If you get anything besides zero ohms, there is a problem. Be sure to measure the resistance of the meter leads by touching them together.
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Unread 04-18-2013, 12:56 PM   #18
ZJNewbi3
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Got it! Thanks everyone! Still didn't rain yet today!
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Unread 04-18-2013, 03:52 PM   #19
ZJNewbi3
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Just back probed the computer (old one) think I'm not getting power will post pics ina bit here (not sure if I'm doing it right)
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Unread 04-18-2013, 04:33 PM   #20
ZJNewbi3
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Here are pics!!! Purple/white (5v) first then black/white (8v) the pink/black (12v) got 0.9V when tested the same way.

When I tested grounds I used the setting so the meter will beep when its a circuit. On pin 11 to battery negitive I got a beep. On pin 12 to battery negitive I DIDN'T get a beep.

I'll try to post vids to YouTube later of this. Also I found grounds on the motor on passengers side, under the alternator, infront of head gaskets. These both beeped with the same ground test used with the PCM. The connections looked good, clean and tight. Only iffy thing is the rusty bolt holding them in.
forumrunner_20130418_173123.jpg   forumrunner_20130418_173142.jpg  
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Unread 04-18-2013, 04:45 PM   #21
ZJNewbi3
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Also I looked at the o2 (I think) its the only wires I found near the exhaust and its also near the oil filter it looks like? But it looks fine. Also the meter is set at "20" on the DC side thought you could see it. The battery was at 11.97V
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Unread 04-18-2013, 06:09 PM   #22
ZJNewbi3
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Here are vid links (no audio sorry) READ DESCRIPTIONS

Testing ground:

Testing power:
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Unread 04-18-2013, 07:17 PM   #23
ZeeJay1997
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Your videos say they are private.

If the ground on pin 12 is missing as demonstrated with no beep, the circuit it is associated with inside the PCM will not function. This is probably why you are getting no voltages.

Check resistance the way I recommended earlier. Most of those meters are set up to beep at a threshold resistance, some up up 40 ohms. I spent a few days on a hot flight line working on a broke airplane everyone wanted fixed now because i was relying on the beep for continuity check. I hate the beep.

Take the grounds on the block apart and clean them. Takes 30 minutes.
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Unread 04-18-2013, 07:21 PM   #24
ZJNewbi3
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Funny story...my uncle stopped by to give a hand and out of the blue he decided to test all the fuses...well one of mine were blown -.- put a new one in and all the powers to PCM come back and I have power to fuel pump. How can I tell? Well lets say my crappy teen-age rush job didn't go to well and gas goes everywhere...have to drop the tank and fix the lines I LEARNED A GOOD LESSON HERE! After I fix that its back to re-testing all the sensors and for spark and such.

THANK YOU ALL FOR ALL OF THE SUPPORT! It's really much appreciated! Didn't grow up working on vehicles much and now I get to get my hands dirty. After I get this thing up and running again hopefully I'll start a build thread!
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Unread 04-18-2013, 08:41 PM   #25
JohnCrabtree
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Quote:
Originally Posted by ZJNewbi3
Funny story...my uncle stopped by to give a hand and out of the blue he decided to test all the fuses...well one of mine were blown -.- put a new one in and all the powers to PCM come back and I have power to fuel pump. How can I tell? Well lets say my crappy teen-age rush job didn't go to well and gas goes everywhere...have to drop the tank and fix the lines I LEARNED A GOOD LESSON HERE! After I fix that its back to re-testing all the sensors and for spark and such.

THANK YOU ALL FOR ALL OF THE SUPPORT! It's really much appreciated! Didn't grow up working on vehicles much and now I get to get my hands dirty. After I get this thing up and running again hopefully I'll start a build thread!
Oooopsie! Haha! We've all done something similar, no worries!

Sent from my iPhone using JeepForum
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Unread 03-01-2014, 12:37 PM   #26
squinty22
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Hey guys I`m a newbe here.First time on forum and still learning how to get around here.I have a 94 GC 5.2.Went thru the whole bit with the no start no spark at coil and distributor, no fuel pump ,and no cel.Got most of that fixed.Found previous owner did some rewiring for the alternator and redid the caps in the ecu.I replaced the fuse block,cps.coil,and ecu.All used except the coil and cps.I now have cel,cranks and starts but dies right away.Like a security issue.There is no security light on in the dash.Starts right up then dies in 2-3 seconds.Any help would be appreciated.Most of the stuff I did was from reading hours of post on here.
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Unread 03-01-2014, 01:31 PM   #27
ZJNewbi3
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Quote:
Originally Posted by squinty22 View Post
I now have cel,cranks and starts but dies right away.Like a security issue.There is no security light on in the dash.Starts right up then dies in 2-3 seconds.Any help would be appreciated.Most of the stuff I did was from reading hours of post on here.
Did you look to see if you have the security wire in the door? I read articles on here telling you how to ground it out so your security will not work but you will get the jeep to run. Search "grounding security zj" in google maybe?
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Unread 03-01-2014, 02:33 PM   #28
squinty22
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i did that already. does the same thing.If the ecu that I got is from a non security vehicle will it work on this one that has security?
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Unread 03-01-2014, 03:43 PM   #29
ZJNewbi3
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Quote:
Originally Posted by squinty22 View Post
i did that already. does the same thing.If the ecu that I got is from a non security vehicle will it work on this one that has security?
Not sure honestly.
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Unread 03-02-2014, 06:48 AM   #30
squinty22
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Anyone else have any good ideas.I don`t want to buy a new ecu to find out that was not my problem.The other thing is the ecu I got from the salvage yard has not had the caps done.Do any of you think this would be worth a shot.Thanks again.
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ecu , no start , pcm

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