I know that the LJ guage clusters are not interchangeable on 05 and 06’s because of some electronic difference. They fit the hole and that’s all.
PCM Failure Potential on 05-06
- Thread starter UND_Sioux
- Start date
The main difference i know of would be the OPDA. you would need to run the 2004 style oil pump drive/cam sensor. o2 sensors may be different part numbers as well.
OP
Not sure I follow. I have an LJ and it is an 06. Do you mean the 05 and 06 gauge clusters are different than the pre-05 clusters?
That's a big assumption. Rumor has it that you change jeeps more often than some people change underwear.
At least I don’t have to worry about my OPDA going bad. We all know that alone is a reason to avoid the 05-06 altogetherThat's a big assumption. Rumor has it that you change jeeps more often than some people change underwear.
JimmyZ
Member
How do I know if my PCM is going bad? Check engine light came on, Autozone ran the code and it said bad camshaft position sensor. i replaced it with a new Duralast one for something like $40. Jeep statred bucking now unpond acceleration. They said i should also replace the crank shaft sensor too.So I did that today. Light it back on and Jeep still bucks?
2005 Jeep Wrangler LJ 4.0L automatic
2005 Jeep Wrangler LJ 4.0L automatic
At least I don’t have to worry about my OPDA going bad. We all know that alone is a reason to avoid the 05-06 altogether
I'm continually amazed that people will spend many thousands of their hard earned dollars on the latest and greatest suspension modifications and chromoly axle shafts but in their next breath object to the concept of paying $105 for an aftermarket OPDA or $575 to ensure that an electronic issue never arises and opine instead that 05-06 TJ automatics should be avoided at all costs.
That's chump change in the spectrum of jeep expenditures.
I am continually amazed that the OPDA thing continues to be dramatically blown out of proportion as if it’s inevitable that it will happen to any 05-06.
P0340 I take it? You'll most often get this code when using any camshaft position sensor other than one installed at the factory. The original OE source went away a long time ago so even a new Mopar sensor is not the same. I don't have a perfect solution but I would bet that the Echlin part from Napa is pretty close to OE
If you're getting P0016, the OPDA is not properly clocked and the corolation between the camshaft and crankshaft sensors is beyond what the PCM can compensate for. If this is the case you'll need to use a DRBIII scanner to synch the two sensors or remove the OPDA and set the engine to TDC.
As for PCM failures: With the auto you'll often see odd transmission temp readings, like 1800-3000 degrees. Another is a harsh 1-2 shift on cold start. This 2nd issue I would suspect is a memory failure due to a bad capacitor, where the PCM is having to relearn the shift points every day.
Another common sign is codes for all 4 O2 heater circuits.
I've only seen one instance where P0340 and crank no start turned out to be the PCM.
JimmyZ
Member
OP
Yesterday I pulled up the 04 Service manual and the 06 service manual and put them side by side on a big monitor and scrolled through the wiring diagrams. There are almost no differences other than the wires that used to go to the PCM and TCM in the 04 now just go to different locations in the connectors on the combined unit. It seems to me that taking a harness along with the PCM, TCM, and sensors from a 2004 should swap over into an 2005 or 2006. It would be a lot of work, but since I'm moving my drivetrain to a new frame, I pretty much have to do some of that anyway.
Yes, if you own an 05-06 TJ/LJ with an automatic. PCM's for these are getting hard to find and reliable refurbishers are even more rare.
However, instead of keeping the refurbed PCM on the shelf, install and test it then mark the original working PCM as "known good" and put it on the shelf. You don't want an untested spare unit on the shelf for years and years only to find out long after the warranty has expired that it doesn't work and there are no replacements available.
At the present time, Mark Cantrell at WranglerFix.com is the only source for 05-06 PCM's that I trust. [@Wranglerfix] I run one of his units in my '06 LJ with automatic and have retained my original working PCM as a "known good" spare.
I have yet to receive a working PCM from the Car Computer Exchange morons.... DO NOT PURCHASE...
All o2 sensors will show bad when good, high transmission temperatures, hard shift from 1st to 2nd when cold and 1600 codes are all signs of a faulty automatic pcm.