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Hate to revive this thread but I experienced the same thing just recently.

Was in Moab last week and Jeep started acting funny. My Jeep started throwing p0032, p0038, p0052, & p0058 codes and the Jeep would not restart. I could clear codes with OBDII Scanner Tool and Jeep would run for about 100 yards then die again.

Was able to get Jeep towed back to the trailhead and on my trailer. Once we brought Jeep back to the house and worked on it for a while, the Jeep ran fine. Grounds checked out fine, battery tested good, alt tested fine, all wires looked fine.

Is this a PCM issue? It's interment which leads me to believe it's not but I could be wrong.
 

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Discussion Starter · #122 ·
Hate to revive this thread but I experienced the same thing just recently.

Was in Moab last week and Jeep started acting funny. My Jeep started throwing p0032, p0038, p0052, & p0058 codes and the Jeep would not restart. I could clear codes with OBDII Scanner Tool and Jeep would run for about 100 yards then die again.

Was able to get Jeep towed back to the trailhead and on my trailer. Once we brought Jeep back to the house and worked on it for a while, the Jeep ran fine. Grounds checked out fine, battery tested good, alt tested fine, all wires looked fine.

Is this a PCM issue? It's interment which leads me to believe it's not but I could be wrong.
TyLeRsLJ,
OP here. Good news is you may not have a PCM issue in IMHO.

My Jeep ran fine with the problem of all O2 sensors showing codes. My issue was the Jeep would not pass the smog test. I was forced to change out the PCM even though the Jeep ran fine. With your Jeep not running properly may indicate you have a real problem and not the PCM.

Hopefully you can get to an experienced mechanic that can hunt down your problem. Good luck and maybe it is as simple as some shorted wires.
 

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TyLeRsLJ,
OP here. Good news is you may not have a PCM issue in IMHO.

My Jeep ran fine with the problem of all O2 sensors showing codes. My issue was the Jeep would not pass the smog test. I was forced to change out the PCM even though the Jeep ran fine. With your Jeep not running properly may indicate you have a real problem and not the PCM.

Hopefully you can get to an experienced mechanic that can hunt down your problem. Good luck and maybe it is as simple as some shorted wires.
The weird thing is that it's not doing it now or once the motor was cooled down. Early mornings in Moab I drove it around 30-45 min without a single issue. It's cleared now and runs and drives great. I had the TSB performed a few years back because the Jeep was never ready for emissions testing so I know that's not the issue.

Did you look up those codes?
P0032 - 02 Sensor 1/1 Heater Circuit High
P0038 - 02 Sensor 1/2 Heater Circuit High
P0052 - 02 Sensor 2/1 Heater Circuit High
P0058 - 02 Sensor 2/2 Heater Circuit High
 

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Early JK's have this problem and it usually turns out to be the driver in the pcm. Being that your's is a TJ and the codes went away I would guess that you have a wiring problem. The heater circuits usually get separate feeds from the pcm but If I remember correct they share a ground circuit with a lot of other stuff. I would start with your ground wires, wherever you can find them, fender, firewall, battery. As with older vehicles don't be afraid to run a couple extra grounds. From the frame to the body and engine.
 
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Early JK's have this problem and it usually turns out to be the driver in the pcm. Being that your's is a TJ and the codes went away I would guess that you have a wiring problem. The heater circuits usually get separate feeds from the pcm but If I remember correct they share a ground circuit with a lot of other stuff. I would start with your ground wires, wherever you can find them, fender, firewall, battery. As with older vehicles don't be afraid to run a couple extra grounds. From the frame to the body and engine.
Thank you for the info. I'm going to try and diagnosis the problem this weekend. I did have a loose negative battery clamp but I don't think that fixed it. It's running fine now so I'm curious to see what happens as the weather warms up and I put some miles on it. The problem only happened when the outside air temp was hot (80 degree +) and with a heat soaked engine.
 

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I don't know how the pcm gets power for the heaters. Your TJ has ignition switched power and relay supplied power. The heaters themselves won't cause it not to run but a power supply problem would. Have a good look at your relays. For the price of them I would change them, or at least move them around. See if the problem changes?
 
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Discussion Starter · #128 ·
I don't know how the pcm gets power for the heaters. Your TJ has ignition switched power and relay supplied power. The heaters themselves won't cause it not to run but a power supply problem would. Have a good look at your relays. For the price of them I would change them, or at least move them around. See if the problem changes?
I'm not sure if this is helpful but might produce some knowledge if there is an experienced person out there.

I was told that the TJ PCM (computer) had the power to the O2 heaters running through the PCM, the problem with that is that voltage could harm the PCM if there was a short within the black box. Supposedly a design flaw. I don't know if this is correct but I was informed of this by an experienced Chrysler mechanic. He thought that this was causing some of the PCM fails.

The computer design should have activate a relay outside the computer box to initiate the high voltage need to the O2 sensors.
 

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Yes the voltage for the O2 heaters run through the PCM. With most vehicles it is a ASD power supply then the PCM controls the heater off and on. It has to run through the PCM so it can be monitored for emissions. We heat the O2's to get them working sooner.
With the JK's the problem was when the ASD relay stuck on it would overheat the board in the PCM and damage it. The vehicle would run fine but would have heater codes for all 4 O2's.
There is no perfect system and the Manufactures are always walking the fine line between cost and durability.
 

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Discussion Starter · #130 ·
Cost was the argument when Morton-Thiokol designed and produced the Space Shuttle Solid Rocket Booster and we know how that faulty design turned out.

Research via Google, replacement 2005/2006 Jeep Wrangler PCM's, you will see that the 05/06 Jeep wrangler have the highest replacement cost because they are in short supply.

My 2005 replacement PSM and install was near $1800 and by the time the dealer was done I had $2200 charge.

Point is the Chrysler PCM design has many more failures than other vehicles. Chrysler, for what ever reason, accepted the design and build and potential failure rate as acceptable. Problem there is they passed on the cost and trouble to those who bought their Jeep while the stock holders gained profit. Thus it shows a low moral code of ethics.
 

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I did have a loose negative battery clamp but I don't think that fixed it.
I wouldn't rule this out. If the clamp was loose that can cause some problems - clamp is the first link in the ground system... A good ground is very important to PCM and sensor functions.
 

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I thought I had this issue fixed but that's a big negative.

Put 500 miles on it since the last time out in Moab. No issues at all. Jeep has been running great around town.

Loaded the Jeep up last week and went to Wheeler Lake here in Colorado. Ran fine all day but coming back down the trail I lost all gauges and the SKIM key light was on. I turned the Jeep off and checked the CEL. The code was for U0155 (Lost Communication with SKIM). Jeep started back up and drove fine for about 100-200 yards then died and wouldn't restart. We started towing it down the trail for about 15 minutes and then stopped. Jeep restarted and ran fine (CEL still on) until I got to the trailer. Jeep died on trailer and wouldn't restart.

SAME CODES AS LAST TIME. p0032, p0038, p0052, p0058. Weird how this only happens on the trails and AFTER the day is almost over. It's weird but all 3 times it happened between 4pm-6pm.

Once the Jeep sat on the trailer all night it fired right up and runs perfect. I said f*&k this and took it to the dealer to run a PCM diagnostics on it. I can't keep having these issues on the trail.
 

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had the 4 bad O2 codes - resolved. - 2006 wrangler unlimited rubicon with 4 liter 6 cyl
first weird thing is my jeep has only 2 sensors, not 4. So I immediately suspected things other than the sensors.
checked wiring for shorts or melting from exhaust, no probs
checked for clooged cat - showed no signs so told myself thats not it
looked for bad fuse or relay, even moved ADC relay into horn position and tested fine
wanted to check everything before contemplating re-soldering the PCM connectors - was not looking forward to trying that unless last ditch effort
noticed that the cable connection closest to driver side slid in and out with ease, the other 2 were very difficult to remove. McGiver'd a solution to press on all 3 connectors - no code for 70 miles so far
UPDATE AND CORRECTION
So ya, there are 4 O2 sensors
And this has worked well for a year. Now, since it is time for emissions testing, the codes have returned. I will check the pcm connectors first, and fuses or relays. And post findings.
 

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Going down this road with my Jeep, replace the cats (much needed) replaced 4 o2 sensors, still threw all 4 o2 sensor codes at the same time, replaced the PCM, passed smog. Now the lockers quit working, I’m hoping this is not a PCM ��Just turned 100k, and yes I have the S on the 8th digit in my vin.
 
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Time to join the 05-06 Rubi ranks with O2 errors. My son inherited my wife's 05 LJ Rubi (auto), lives about 1.5 hrs away, and had several inspection issues. I lent him my 04 TJ Rubi back in Dec while I had an extended vacation. The LJ always had one O2 that would throw an error unless we got gas at this one station. We would go there prior to every emissions test. After getting him new tires, replacing brakes at all corners (and filling divots from the pad ears), a water pump that blew suddenly with no weeping, oil leaks, and a few other issues, the LJ suddenly had shifting issues (hard shifting, not shifting till 3000RPM+). I checked the codes (expecting just the one), and had P0031, P0037, P0051, P0057, P0700, and P0562. The alternator tested clean (14.3v DC, diodes good, 0.03 AC), but battery was a hair low and failed the shop test, so I swapped it out. When the P0700 became a permanent MIL, the gears started slipping. Reset codes and tranny went back to hard shifting. I'm hoping the P0700 is a side affect of the power issue. Replaced all O2 sensors (w/o any expectations) and no change. Checked wiring from PCM plug to each O2 plug. Check PCM plug out to PCM plug in. Checked grounds. Checked all non-grounded circuits for shorts to ground. All good.

I sent the PCM to G7 and they said they found no hardware errors, but saw software errors and re-flashed it. I'm a little skeptical about this answer. Plugged it back in and the errors returned. O2 errors where immediately permanent MILs with corresponding pending errors.

I saw a trick online where you cut the connector off an old O2 sensors, plug it into the harness, and connected the heater leads to a head light. When I started the jeep, the expectation was that the heater circuit would turn on the head light. However, it did not. By mistake, I turned the key on, but not to start, and noticed the head light powered on for a brief period. I heard a click from the PDC and tracked it down to the ASD relay. After some research, I found out that the power systems cycles 'on' with the key, but shuts down after around 1.8 second if not started as a safety feature (fuel pump shuts down as well as other items). I was getting 5.2v across the head light pins. So now I know the PCM is able to send power to the O2 heaters when 'on', but not when the jeep is running. I rigged a test where I ran 12v through the PCM plug to the heater circuits, and check the volts on the signal side at the PCM plug. Within a few seconds of power, the O2 signal circuit started registering a voltage. Long story short, all four O2's heated enough (proving the heater worked) to start receiving O2 signals through the other circuits.

I plan to reach out to G7 tomorrow. Since I can't find any PCM schematics, my thought is the P0562 might have something to do with voltage being sent to heater. It can send enough juice when it's not running, but can't when it is. I'd hate to have to replace the PCM after all the horror stories with the TCM, SKIM, etc. We'll have to see where this goes.
 

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Seems like an odd error, but hopefully you've narrowed it to the problem. In for the fix.
 

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Discussion Starter · #137 ·
Original poster here. Just saying there is hope. After my nightmare PCM problems and finally having the dealer find and replacing it, my Jeep has been running well and dependable. I actually sold it to my neighbor and can look across a couple acres and see it in the pole barn.

He is delighted to have an 05 Rubicon TJ and one built up like new.

Coming down a tricky fin in the trusty Rubi 2017, Moab UT
 
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