5v reference issues
CF Veteran
Joined: Nov 2017
Posts: 3,700
Likes: 238
From: Groton, MA
Year: 1995
Model: Cherokee(XJ)
Engine: I6 4.0L
CF Veteran
Joined: Nov 2015
Posts: 2,856
Likes: 201
From: syracuse ny
Year: 1997
Model: Grand Cherokee (ZJ)
Engine: 4.0, new lifters valve job with new springs and exhaust valves, preload set with shims
Are you saying you have 5vdc on two of the three connections on all those sensors? That is a fault for sure. Disconnect them one by one and see if one is causing that. Other than that the next thing I would check would be the wiring harness for a short to the 5 v .
Thread Starter
Newbie
Joined: Dec 2018
Posts: 8
Likes: 0
Model: Cherokee (XJ)
Info from original post
ell....i have a 97 xj w/ax15.....260k miles.....ran great until a few days ago. She started sputtering on the interatate like there was a fuel issue. Gauges began acting erratically...then it self corrected. Began acting up near my house...made it home and popped the hood while it was still running. Jiggled wiring harness near fire wall, problem stopped, then reappeared...jeep died and has not started since....naturally, i assume i have bad/broken wires in harness...replaced harness and still will not start. Replaced cps, still wont start...checked/cleaned all grounds and still wont start. I have power at asd relay and 5v at sensors....i have checked O2 sensors for shorts.......i have no flippin idea what to do from here....i refuse to go to a mechanic....please help!!!
Trending Topics
CF Veteran
Joined: Nov 2015
Posts: 2,856
Likes: 201
From: syracuse ny
Year: 1997
Model: Grand Cherokee (ZJ)
Engine: 4.0, new lifters valve job with new springs and exhaust valves, preload set with shims
OK are we still saying we have 5v on each of the sensor signal wires with all the sensors unplugged? Because each signal wire for each sensor has a different signal depending on the output signal of that device..
CF Veteran
Joined: Mar 2016
Posts: 3,816
Likes: 725
Year: 96
Model: Cherokee (XJ)
Engine: 4.0
ell....i have a 97 xj w/ax15.....260k miles.....ran great until a few days ago. She started sputtering on the interatate like there was a fuel issue. Gauges began acting erratically...then it self corrected. Began acting up near my house...made it home and popped the hood while it was still running. Jiggled wiring harness near fire wall, problem stopped, then reappeared...jeep died and has not started since....naturally, i assume i have bad/broken wires in harness...replaced harness and still will not start. Replaced cps, still wont start...checked/cleaned all grounds and still wont start. I have power at asd relay and 5v at sensors....i have checked O2 sensors for shorts.......i have no flippin idea what to do from here....i refuse to go to a mechanic....please help!!!
know of cases where this has been the issue. In the case of a pre-97 a compatible wreck computer can be swapped straight in.
I believe from 97 on, things are more complicated. Rock Auto sell them.
probably worth unplug & check computer harnesses
CF Veteran
Joined: Nov 2015
Posts: 2,856
Likes: 201
From: syracuse ny
Year: 1997
Model: Grand Cherokee (ZJ)
Engine: 4.0, new lifters valve job with new springs and exhaust valves, preload set with shims
Does sound like an internal pcm connector issue. I am about to dissect mine, but mine is different than an xj. Still, you may benefit from this video on how to fix cold solder joints www.youtube.com/watch?v=-cAt9HhbBcY&feature=youtu.be
To replace the PCM you have to have it flashed with your VIN and mileage which adds a costly step, as alluded to in the previous post.
To replace the PCM you have to have it flashed with your VIN and mileage which adds a costly step, as alluded to in the previous post.
Last edited by 97grand4.0; Dec 9, 2018 at 07:40 AM.
Thread Starter
Newbie
Joined: Dec 2018
Posts: 8
Likes: 0
Model: Cherokee (XJ)
Fixed! Without a mechanic!!!
Apparently, the ground inside the pcm was bad...sensor ground wire, A4, had no conductivity to A31 or A32. I cut the ground wire, A4 at the pcm and ran it to the dipstick ground. Jeep fired right up and idled smooth up with no codes! Thanks for everyones help! Thanks especially to scanner danner on you tube for having the ONLY video that shows how to test a CPS with a multimeter
CF Veteran
Joined: Nov 2015
Posts: 2,856
Likes: 201
From: syracuse ny
Year: 1997
Model: Grand Cherokee (ZJ)
Engine: 4.0, new lifters valve job with new springs and exhaust valves, preload set with shims
Apparently, the ground inside the pcm was bad...sensor ground wire, A4, had no conductivity to A31 or A32. I cut the ground wire, A4 at the pcm and ran it to the dipstick ground. Jeep fired right up and idled smooth up with no codes! Thanks for everyones help! Thanks especially to scanner danner on you tube for having the ONLY video that shows how to test a CPS with a multimeter
Thread
Thread Starter
Forum
Replies
Last Post
Guntar13
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
2
May 15, 2012 11:35 AM
kaustickollapse
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
2
Aug 31, 2009 04:46 PM
johnnyrossman
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
4
Mar 22, 2009 12:54 AM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
