More 47RE automatic transmission LIMP MODE discussion
 

OK...I have read every thread there is on the net on this 47RE limp mode problem and I still can't get mine resolved.

Truck- 1997 3500 CTD

Symptoms - no first gear starts, no overdrive, poor lockup, 1st gear can be manually selected only if neutral is selected before dropping to first, manual upshifts firm and solid.

What we have done so far - new transmission electronics: the Torque Converter Solenoid, the Overdrive Solenoid, and the main body for the solenoid with the wiring harness on it.

CODES- Truck is still coding the TCC code and the OD code. Makes no sense since we replaced them so something else is screwed. How common is corrupted software where a reflash cures this? I have heard not too often.

TPS appears to be fine.

Trans shop is clueless...I already know more than them. Dealer is sketchy - I bet they try and sell a rebuild rather than ctually troubleshoot it, and then tell me something else is still wrong after they rebuild because they never diagnosed the real problem first.



I have a pinout and would like to confirm that we need a 5 volt source on the B31 ORANGE wire going to the transmission correct?

If I don't have that voltage, what the heck can shut it down? Battery Temp sensor? Trans Temp Sensor? WHAT? I will check the POWER DISTRIBUTION CENTER and make sure the relays are relaying and that power is leaving there for the transmission relay.

HELP......what to do next

My 2001 lost 1st gear and OD at one point. I pulled the trans relay and put the jumper in like is done for the torque converter lockup switch. It shifts fine now and I have the "mystery" switch for manual lockups.

No one has ever been able to tell me why this worked or what exactly that relay does if the truck shifts fine without it.
I checked the relay and it was fine.

have the trans shop check the line pressure at full throttle. high line pressure will make it go to limp mode just like you discussed. also, you can take the large electrical connector up on the driver's side of the trans, and clean both sides out with brake cleaner. be liberal with the brake cleaner, it will all evaporate. sometimes, salt likes to build up inside poorly sealed plugs, and will show a low resistance between the input and output signals of the governor pressure sensor. this will make it think that there is a high line pressure.

hmmmmm dosen't go into first? so it starts in second..... if you manually select first and as it starts rolling put it in drive when it shifts does it skip 2nd and go to 3rd? if so then it is a line pressure issue and you need to install a voltage limiter inline with the Gov pressure sender wire in the harness..... also there is a sensor on the rear of the tranny.... from the tailshaft there is the speedo gear at aprox 9 o'clock IIRC and then a little farther forward at 7 o'clock there is a sensor that has 2 wires going to it..... this seems to me like it is your problem...... if the sensor was replaced the pins may not be the same size (slightly different per manufacturer) or the plug may be worn out from the constant vibration...... you need to go to Dodge and buy the new plug that comes with about a foot of wire with the ends already on them, heatshrink, solder connectors...... the part number is 1-05013950AA i'm not sure how much it is but that would be my first guess......

Chrysler would rather pay to put a rebuild in, than have their mechanics digonose the problem. Thats how their warrenty works, if you can't digonose it w/ a scanner, and fix it.. They'll most likely replace the whole thing.

Like a valvebody, if a valve is sticking, or if a solenoid is shot, they'd rather pay to have a whole new VB put in than rather pay the mechanic labor rate to digonose the problem and fix it.... thats just how they are, its getting worse and worse...

I'll write more on this subject tomorrow.

Hmmh...I just replaced the computer on a 2000 Durango 4x4 w/360 v-8 with the same symptoms last month. Had the Tcc codes and something else concerning the powere relay and I checked the pin outs and condemned the computer. Had a quote from two ecm rebuilders for $225-$250 range. Replaced the computer and it's fixed.

Anyone?
 

Who has had the more problematic AUTO troubles and actually found the true cause?

How many times has a dealer reflash actually been required?


I know of the line pressures. At this point it would seem that all internals are intact. The insides look clean, the fluid is unburnt, the filter has remained free of particluate matter, and the transmission is holding solid at a consistant level of lockup and predictability.... At least this far the transmission appears to not be burning up, but for how long on these test drives I do not know.

Like I said, I don't even trust a dealer because they don't even know enough to put it into first manually to test drive it. They seem completely inept.

NO CHECK ENGINE LIGHT and only the two codes. When the codes are cleared they DO NOT immediately re appear without operation for a few minutes.

Please help me further on the pinout voltages. I have found the material on this particular subject to be VERY lacking on the forum. [verymad] I have the ALLDATA pinouts, but they are vague. Some say a 12 volt source on pin 1 (which seems wrong to me) and some say a 5 volt source on wire B31. Which is it?

**OR more like what color wire- what volt AT THE TRANSMISSION CONNECTOR?[duhhh]

Come on, I know someone knows this....I know we can fix this.

thanks

obviously you didn't try this yet...... ask me how I know it works?

oh ya and fill in your signature so we know what year and model of truck you have.......

The speedo works and there are no codes coming up for the speed sensor being bad.

This is a voltage pinout issue or an ECM ground signal issue I am fairly confident.

I just have a partial database on the pins and the voltages at this point.

Ususally the won't shift out of first gear issue relates to the speed sensor from what I can tell...my problem seems to have been cured for most people by the solenoid pack replacement and that is what codes are showing on ours, but the replacement of those parts didn't fix it.

Must be control grounds or voltage issues relating to these sensors and solenoids

that's not what i was pointing out.....

let's try this again...... i didn't say anything about you speedometer.... just using it as a reference.... fix this and i'm 99% sure your tranny will start working correctly.....



correct.... but you never stated until now that it wouldn't shift OUT of first.... you said it wouldn't START in first.....

also make sure that the plug that the main harness (the one that the reverse circuit, neutral safety, speedo and that other sensor i was talking about) where it plugs in is clean of moisture and debree.... also make sure it hasn't come unplugged.....

It is in limp mode...It WILL NOT start out in first- no automatic upshift, no overdrive. I was under the impression that the speed sensor cause the problem where the trans would not shift OUT of first.


All connectors are on, how good of conections can only be judged by the fact that when the connectors are off, the truck won't move, so I assume when they are connected they are making contact.

I have 5 volts on the B31 wire.

HOWEVER with the key on, engine off, I have no voltage at the 3 pin connector on the transmission by the shift lever. Is the voltage here ENGINE ON ONLY, or alternator field dependent? Also which wires are ground from PCM and which one is hot on that plug?

I found a taped section on the orang B31 wire by the PCM and will check it to see if a resistor had been installed or a splice in due to previuos monkey business going on. Maybe someone had put a transgo kit in it or something before we got it.

I will throw a speed sensor in it as well...15 bucks, but I don't see it causing the two codes for the governer and the TCC.

interesting..

http://i9.photobucket.com/albums/a78...odgetranny.jpg

ok check Number one on the picture.... that should be the connection for lockup and the other various solenoids/gov. pressure sensors..... number 2 should be neutral safety and reverse lights.... and number 3 is the output speed sensor... it is magnetic and may need to be removed and inspected for metal shavings.... but this is where i said to check first on your problem. above is the part number that i believe you will need to fix your problem. my tranny has a sensor with a gear that sends the signal for my speedometer that is at the 9 o'clock position on the od unit... where that flat spot is.... don't know if yours is different...... but i'd check that speed sensor first....


that's my .02 check it if you want....

What I meant by no voltage to the trans was on pin 1 of the multi pronged plug...not the 3 pin.


OK-did you lose OD and 1st gear and the culprit was a bad speed sensor?

That socket hex head removed thing on the OD is the speed sensor.

The electronic governer solenoid in the tranny could be the culprit, they have been known to "stick"