LIMP MODE - code 0403 chrysler 300 2006
 

My car is a nightmare. Literally has been in and out the shop for the last 3 years.

My car would go into limp mode. It does not accelerate and feels likes its about to die but doesnt. I've changed my 02 sensor, throttle body, egr valve. and new pcm. The code i get is 0403. I brought it to the chrysler dealership and they just eyeballed the problem telling me its my egr value (no its not, **** you). I told them that the pcm is giving a lot more than one error code. they come back and tell me it is possible a bad pcm that i changed a little over a year ago.

It can possbily be a bad pcm bc i did buy it online. But i've done endless research and i think it maybe a bad catalytic converter? Please HELP! its a money pit!

I forgot i changed the crankshaft sensor and map sensor as well....

I fail to mention it happens more frequently during the summer. DUring the winter it runs normal...weird...

ok mmm limp in mode if for the transmission nothing to do with the engine .
With all of what u have said U have replaced still dont know what u are asking what are some codes and who changed all this stuff out?

"Limp mode" = rough idle, cannot accelerate. What i'm asking is what other possibility can be wrong with the symtoms my car is having....

Chyrsler changed few of the parts and a local mechanic shop did the rest.

ok wrong terminology then limp in mode is for the transmission only when its in second gear there is not any sorts of mode for an engine. What are you currant codes in the computer?

Get hold of a 30,000 microfarad capacitor of at least 16volt working, and wire it temporarily with clips across the battery. This will be an electrolytic capacitor which is polarized and therefore will need to be wired across the battery the right way round, +ve. to battery +ve. etc.
You can get these at radio/electronics shops, or maybe find one in an old computer power supply. The capacitance is not critical but the voltage musn't be less than 16volt. Even if you have to pay for it, you're looking at a few dollars at most.

If it works, wire a 10amp. slo-blo fuse in series with the +ve. lead and install it properly so it doesn't flop about.

Oh, and report back if it does work. No guarantees of course.

Leedsman.

Leedman are u Fing serious? What in gods green earth are u talking about it has ZERO info to contribute to this post I have seen all your others ones as well its its simply adding fluff to cotton candy.

I'm not quite sure what "Chrysler-Tech" means by the expression 'Fing serious', HOWEVER---

I had constant problems with the MIL lamp coming on and "restricted performance" shown in the window of my previous car, an S-Type diesel Jag. It could do it anytime anywhere. That car also had a number of micros controlling such as engine, transmission etc. just like my current Chrysler.

Having much experience with microprocessor-controlled machinery, I knew a micro controller is only as good as its power supply. Our statistics at ADT showed over 50% of control faults for muxs., panners, lenses etc. turned out to be the power supply to the controlling micro. Usually, an electrolytic capacitor had gone dry and wasn't working properly, leaving switch-mode "hash" on a power line. (This was a stock fault on a certain Panasonic video recorder -- famously).

The power supply to ALL the micros in a car is, guess what, ---

THE BATTERY.

After installing the 30,0000 microfarad capacitor on the Jag's battery, the problem stopped, and stayed that way for the next three years until I got shot of the car.

Explanation:--

Lead-acid batteries are known to "resonate", more so as they age through the service life. This resonance is held to be anywhere between 2 and 6MHz. Now it just so happens that the clocking frequency of many micros usually lies in that bandwidth. Lead-acid batteries have a very low internal resistance indeed, say .01 ohm, but a battery IMPEDANCE (like a/c resistance) can be very different, esp. as it ages. This can aggravate the situation. A 30,000 microfarad capacitor wired across the battery will drop the impedance of the battery to near zero. In fact I went the whole hog and wired a small tantalum capacitor as well just to make sure the battery impedance was as low as poss. (Tantalums have no ESR, Effective Series Resistance).
Each micro in the car often has more than one clock Indeed the home computer I'm using now will have at least six. So it's just not possible to know EXACTLY what's going on when there's a fault, it's all trial and error in this instance of trouble-shooting.

So this resonance can upset micros. The answer could be a new battery at £150 or so, or would you prefer a few dollars for a capacitor to do the same job? Whatever, it costs so little to at least try that avenue, and the OP seemed to be getting desperate, and I felt a little sorry for him and the troubles he's having with his Chrysler. However, I'm the first to say there's no guarantee. Even the car manufacturers can have their control micro problems, famously Toyota with sudden uncontrolled acceleration in some of their cars.

One would hope that this explanation helps, Mr. Chrysler Tech., but one does appreciate that electronics can be difficult and counter intuitive to someone not so inclined.

Leedsman.

first this is not a jag or a diesel or a UK spec car
The systems u are talking about are way different then ones you will find on any shelf in a store.

This guy is complaining about a rough idle not a battery issue nor a battery drain the battery theory u have described in such detail is irrelevant in this matter. Battery drop or frequency is then again irrelevant in a cars issue. Why because the alternator is charging up the battery and running the whole car. The voltage will change based off the currant needs of the car so they are ever changing and FYI u are comparing apples to oranges in the power supply. Home computer use AC currant with a steady 110 or 220 vol source it must be the same. Cars use alternator which makes ac and converter it to DC and it will change from 13 volts to 14.4 volts and 50 to 110 amps depending on the car. And Chrysler cars the slowest Clock speed was 14mhz if i remember right old technology the new cars use up to 600mhz data buses so your 2-6 mhz frequency deal is once again irrelevant. Also the engineers that design the cars kinda know how this system works they designed it know know about frequency and latent heat and all of the wonderfully items of and engineer. A battery used on a Chrysler serves two proposes one starting power to get the car running.
Second a charging post for power from the alternator and a buffer for any voltage spikes that's it U can remove the battery and the car will still run.

As I've said many times, there is no guarantee here, the message is, TRY IT. It worked for me.
So far the OP's problem has NOT been solved.

The first line of the OP's complaint reads -- (copy and paste)

"My car would go into limp mode. It does not accelerate and feels likes its about to die but doesnt".

Notice the expression, "limp-mode". This is commonly held to be the same as "restricted performance".

Much is being read into my last posting that isn't in fact there. It has nothing to do with other postings regarding battery charging. So is "irrelevant".

Warning: "Chrysler-Tech" appears to be saying "U can remove the battery and the car will still run". (Last sentence). Under no circumstances should the battery EVER be disconnected while the engine is running. The alternator will immediately rise to a dangerous voltage and ruin any processor board connected to the 12volt line.

I'm astonished anyone could say such a thing on a website like this.
None of this posting by "Chrysler-Tech" seems to make much sense either.
I have no confidence in this man's opinions whatsoever.

I will make no further comments on this matter as it is obvious where it is going.

Leedsman.

U really want to argue with me about this? With a 17 years of Chrysler experience u really want to argue with me about how a system works on a car that I have had extensive training in?

Limp in mode is for transmission not engine performance look it up for yourself.

And no disconnecting a battery while a car is running will not make a voltage increase and damages your computer why because the computer is already controlling the ground to which makes the alternator that uses a pulse with modulated duty cycle aka ON AND OFF to regulate the voltage and its not a 12 volts system that the computer uses any way if that were the case they whey is the alternator putting out 13 to 14 volts?

Im not the one making sense I think your the one just rambleing on and on about nonsense All of the info u provided is pretty much useless to a car or any member on this site. IM sure u are a great computer engineer or microprocessors guy but have zero experience in dealing with matters of a car.

[QUOTE=CHRYSLER TECH;73023]first this is not a jag or a diesel or a UK spec car
The systems u are talking about are way different then ones you will find on any shelf in a store.

This guy is complaining about a rough idle not a battery issue nor a battery drain the battery theory u have described in such detail is irrelevant in this matter. Battery drop or frequency is then again irrelevant in a cars issue. Why because the alternator is charging up the battery and running the whole car. The voltage will change based off the currant needs of the car so they are ever changing and FYI u are comparing apples to oranges in the power supply. Home computer use AC currant with a steady 110 or 220 vol source it must be the same. Cars use alternator which makes ac and converter it to DC and it will change from 13 volts to 14.4 volts and 50 to 110 amps depending on the car. And Chrysler cars the slowest Clock speed was 14mhz if i remember right old technology the new cars use up to 600mhz data buses so your 2-6 mhz frequency deal is once again irrelevant. Also the engineers that design the cars kinda know how this system works they designed it know know about frequency and latent heat and all of the wonderfully items of and engineer. A battery used on a Chrysler serves two proposes one starting power to get the car running.
Second a charging post for power from the alternator and a buffer for any voltage spikes that's it U can remove the battery and the car will still run.[/QUOTE
I have a different question for you and it doesn't pertain this at all. I have a chyrsler 300 with 5000 miles on it. It seems that I have cold air coming out of all vents when the temp is set on high and sometimes the direct opposite will happen with heat coming out of the vents and the temp is set low. I am taking it to the dealer this Wed. for them to look at. This problemis occurring when in the manual mode. In the AUTO mode it seems to work ok. Thank you

Visit a dealer for warranty issues dont try and repair yourself it could void your warranty

It's what happens when a new member can't figure out how to start a new thread.

Similar issue
 

I have a 300 Touring 2006 with the same problem (limp mode) more intensive in summer than in winter
Appear generic problems with speed sensors
I have them changed and still failing
Well, I need to know what to do with the ECM since some techs
refer to it as the problem, sending me to the dealer
Additionally, I have no ground in the AC, so it doe snot work
Techs tell the problem is in the ECM also
Is there a way to have the ECM reset by someone different than the dealer?
Thank you in advance for your answer...
:)

First what are the codes for the prob you are having?
Then what engine side and type of transmission do you have?

Have you had your car on a scope yet? Check the wave forms from the cam & crank sensors and relate them to ignition and injector wave forms. Your cam sensor could be the issue. The vehicle will start, (although it would start a tad slow) idle fine but run rough as the fuel timing would be off. You could compare the wave patterns to know ones on vehicles that run well.
Good luck.

Thank you very much for your responses. This is related to the same symptoms that were reported at the beginning of this post by dinhle504 on 08-27-2013, 01:05 PM

The issues are:
- Suddenly, the transmission goes into 'limp mode', not allowing me to accelerate more than 40MPH and keeping that speed or lower only.
- The transmission is not capable to fix itself. Solution posted in Internet. Shut off the car and start it on again. No problem.
- It fails all the time during summer. During winter almost never happens.
- When it is in 'limp mode' (automatically and in order to protect the transmission) there is no way to go to manual gears (moving the gear side-to-side does not change the status).
- Very common and after changing speed sensors could only head to the BCD/ECM malfunction. So, it is a problem with the computer? If so, it needs to be reloaded?
I believe that doing this on the dealer will cost more than the real value of the car...

The codes are:
P0700 OEM Brand: Chrysler
Transaxle control system fault
ECM received a signal that the transaxle control/module has a fault
Cause:
a. Shorter or open circuit within transaxle;
b. Failure of transaxle control module

P2767 OEM Brand; Chrysler
Input speed sensor 2 circuit no signal
The TCM has detected a correlation error between the two input speed sensor signals
Causes:
a. Open or short circuit condition;
b. Poor electrical connection;
c. Failed input speed sensor 2;
d. TCM fault

At this time, I really believe that the car at only 125000 miles (failing since 90000 miles) is not as good as it looks. For example, I have no ground for the A/C so nobody can fix it because it goes beyond the A/C shops knowledge. Apparently the ECM is also guilty and I have to take the car to the dealer and the extended warranty does not cover since it is not mechanical but electronic circuit related. Fortunately, this summer was not so hot here in MI.

Thank you

Well, not quite the same issue...Sounds like an issue with your speed sensor or the wiring to the TCM, or the TCM itself. Low fluid level can trigger the same issue, however I have to "assume" that it was checked. As to the A/C issue, rodents can cause havoc with wiring issues at the PCM. Good place to start.

Probably not the same issue but the same symptoms and the same recommendations to solve them that never worked. If the problem was wiring, that was already carefully checked, it would not fix itself after stopping, shut off the car and just start it again w/o problems. I read it in multiples blogs about Chrysler 300 transaxale problems and how to solve them quickly after expending time with the dealers w/o solutions. Let me add that it is pretty common to change the PCM (by direct Dealer recommendation) and nothing is solved. Looking around for other blogs, you will find many 300 owners with the same problem... and no solution, at this point. Thanks

The codes I have issued in detail on my reply on 07-06-2014 04:28 PM
P0700
P2767

The car is a 2006 Chrysler 300 Touring 4dr Sedan (3.5L 6cyl 5A)

-Transmission standard at 125000 miles
-Speed sensors changed
-Fails mostly on summer (all the time)
-Drives up to 40 MPH w/o issues and then gas pedal does not respond and
keeps the speed (limp mode) until stop the car, swith off, switch on and it works properly again. No more fails after that (next start will fail for sure)
-Engine light on and off
-When entering to limp mode, jerk gear changes are issued
-Manual option (1-2... ) does not work during limp mode
-When fails, even R does not work, only D at 40 MPH

Apparently, the ECM or TCM could be the cause. I would liek to know if thee is a way to know for sure, before going to the dealer to listen that everything muts be replaced...

Thank you

2767 input speed sensor signal circuit PCM for this?
Have you not at least triad the speed sensor first?

Possible poor connection at speed sensor.
 

I have seen issues with the connector at the speed sensor cause this problem. Yes, shutting off and re-starting is a temp. fix, as the TCM re-sets before sending your speedo crazy and posting the code again. Remove the connector, clean with a throttle body cleaner, apply some contact "goo" and attach. You may also want to replace sensor to be sure. Good luck.