Recurring Limp Mode
 

Hi, I am a disabled driver in the UK and own a Chrysler LX Grand Voyager (Graz built GS). It is equipped with the 3.3 L Petrol engine and the 41TE Autotransaxle with a total mileage of 140,000 on the Odometer. The vehicle is serviced regularly and ordinarily runs faultlessly.

Eight weeks ago the vehicle suddenly failed to engage 3rd gear whilst gently accelerating before dropping into limp mode. Immediately before this occurred the engine very briefly cut out twice (almost a misfire as re-engaged instantaneously), this had occurred randomly on several previous occasions during the preceding 3 months but had NO adverse effect on the transmission shift so not sure if this is even relevant.

Unfortunately as my income is extremely limited taking the vehicle into a dealer is outside of my budget. Maintenance & repair is therefore conducted with the assistance of friends or through smaller shops who's expertise is limited.

With this in mind the diagnosis of this issue has been limited to reference to the Internet with assistance from OBD fault code checking at a small (non transmission specialist shops). No codes were obtained and communication with the TCM was not possible.

Whilst there were many of these vehicles sold in the UK it appears few garages possess the diagnostic software which can interact (other than occasionally on a very basic level) with Chrysler's onboard OBD II diagnostic/programming system. Thus it is possible that the lack of transmission fault codes may be indicative of equipment incompatibility and thus a failure to recover any codes RATHER than a total absence of any codes in the first place. Thus it is perhaps a false negative?

In the process of troubleshooting this transaxle issue, the fluid (Mopar ATF +4) was checked for level and condition. In fact the mechanic considered the fluid to be in such excellent condition (neither burned, contaminated nor discoloured) that he chose to reuse as much as he could before topping the level with fresh Mopar ATF +4. The filter & gasket were also replaced, noting that the pan magnet was found to be totally clean on inspection without even the faintest trace of metallic deposits.

Subsequently both input & output speed sensors have been replaced along with the shift solenoid using the latest available Mopar OEM replacement (new) parts.

Despite all of the above remedial actions the vehicle continues to fail to engage 3rd gear and above and simply drops back into limp mode.

I would very much value any suggestions, thoughts, assistance you might be able to offer as what/where to look next. Also any guidance on replacing the TCM (I have one sitting on a 98 LE with a damaged engine I keep for spares) and what is involved (what, if any, re-programming is required) other than disconnecting and refitting?

A .pdf of a 2000 NS Diagnostic Procedures Manual for the Transmission would also be very helpful if any forum members can assist or point me in the right direction. NB. I have the Powertrain Diagnostic Procedures Manual but this does not really cover the A604/41TE Transmission and how to troubleshoot any issues (especially electrical) in situ.
All/any help you can offer will be very much appreciated.

Many thanks,

Voyager Pilot

As you are an impecunious user like most of us here, do the simple cheap things first. Disconnecting the battery -ve for a few minutes; then reconnecting may remove the fault for a while. If so, the control micro has been garbaged by spikes on the 12volt line.
If so, consult the various postings on here as to remedies.

Leedsman.
n.b. This procedure may lose the radio code, but not necessarily.

All manuals are here all service manuals are here, key dance [will not do transmission codes] is here.

If you live within striking distance of Cambridge area ask for tfb on this forum. at the least he'll give you a free main stealer level diagnostic read and good solid advice. Best of luck.

Manuals
 

Hi QinteQ and many thanks for taking the time to post the links above....I have used this site previously and have an excellent collection of manuals from there (this is where I got the Powertrain Diagnostic Procedures Manual from). The site has a Transmission Diagnostic Procedures Manual for the RG but NOT the one for the GS 😟

The GS Powertrain Manual has very little on testing the Transmission whereas the RG Transmission Manual is very comprehensive in that respect. So still trying to find one for the GS.....

Thanks also for recommending the services of tfb....I'm located in the North West (Merseyside/Cheshire area) unfortunately......don't suppose you are aware of anybody around these parts?

......Just thinking would tfb be able to reprogram/recode the TCM from the spares vehicle? I could maybe post it to him???

Welcome any further thoughts....

Regards

Voyager Pilot

Voltage Spikes
 

Hi Leedsman...Thank you for your response much appreciated....not sure if I'm doing the right homework here on voltage spikes......are we talking about the capacitor attached near the battery or am I missing the point entirely?

Thanks,

Voyager Pilot

The capacitor across battery was a method of stopping MIL lamp coming on with an S-type diesel Jag. many years ago. By "squashing" the spikes at source it stopped them getting into memories various, garbaging data-bytes. Usually, the battery does the same spike-squashing, but due to age and possible sulphation it can fail to do this. For an electronics amateur, prob. the easiest course is to substitute a known very good battery then "suck it and see". MAKE SURE POLARITY IS CORRECT WHEN CONNECTING SUBSTITUTE BATTERY. Otherwise much grief. Some batteries have the terminals reversed with respect to the original. If problem gone, all is good. See that the connectors are not corroded. Costs nothing if you borrow the battery. Another method is to strap a second battery across the main one with jump leads, put the second battery wherever convenient, (like the passenger footwell, leads through the open window) and go for a run. If problem gone, you know what was causing it.
When connecting and using a second battery like this ENSURE POLARITY IS CORRECT. MAKE SURE THERE CAN BE NO "SHORTS" ESPECIALLY RED + TO CHASSIS OR ANY METALWORK. STARTER BATTERIES CAN EASILY SET THINGS ON FIRE. DO take great care over this one.

Leedsman.

Voyager Pilot,

Can't auto-shift into 3rd sounds like a non software hard issue, but can you handball the auto stick from low to 2 then 2 to 3 and leave it in 3 - does it engage and drive in 3rd ? and does it then go to 4 and down to 2 ?

Leedsman #6 'sulphation' issue :

You might have a posh charger that will de-sulf and recover deeply discharged [or in 2014 where it has simply slipped below the minimum voltage threshold of a modern charger and the charger doesn't know what to do with the battery] batteries, the old school method REM was the ‘in series’ from trucking days late 60’s early 70’s. You need :

- old school [or modern do anything] battery charger
- jumper leads
- a know good battery @ above 12.2 v [AGM Calcium, spiral or flooded it doesn't matter]
- your dead, deeply discharged battery
- a watch or timer

Without having the charger connected to the battery or turned on at this stage, go parallel - positive to positive and negative to negative. Now, hook up the good battery to the charger, turn on the charger. The charger will "see" the voltage of the good battery, and start providing a charge.

After the batteries have been charging for about an 60 minutes, check to see if the dead, deeply discharged battery is slightly warm or hot to the touch. Batteries naturally become warm during charging, but excessive heat may be an indication that there really is something wrong with the battery. Also discontinue the process if you hear the battery "gassing"-a hissing sound coming from the safety valves. If it's hot or gassing, STOP CHARGING IMMEDIATELY!

Check back every hour to see if the dead, deeply discharged battery has charged to 10.5 volts or above. If it has, disconnect the charger from the 13a socket and remove the good battery from the charger. Now, connect only the dead, deeply discharged battery to the charger. Turn on the charger and continue until the dead, deeply discharged battery reaches a full charge, or until the automatic charger completes the charge process. In most cases, the dead, deeply discharged battery will be recovered.

Hi Leedsman/QinteQ...Thanks for the info...much appreciated.

Leedsman do you think I should connect the proposed capacitor at this stage? I assume that this is to rule out existing voltage spikes?

QinteQ to give you more details, when I dropped the car off with chap who is trying to fix it for me I took him for a brief test drive to demonstrate the limp mode issue. He asked me to manually select 3rd (which I hadn't done before) it engaged and shifted both up & down. At this point we stopped and switched off to reset the system. The car was started up and drive selected and of course rapidly dropped to limp mode. As far as I am aware manual selection has not been tried since.

Hope this helps,

Voyager Pilot

Auto gearbox's I'm sure you will agree are in the realms of the 'dark arts department' most of us don't really understand them since the invention of [computer run solenoids] the CANBUS and then the different speed hybrid PCi & CANBUS's running at different speeds moderated by the BCM and routed by the PCM in the same vehicle. I've always try to avoid 'parts darts' without an accurate starting point which is a competent 'read' of the 41TE errors. Its encouraging that if you can handball the auto box in manual mode 1 2 3 and get it to auto-shift up and down as per normal it suggests its soft or sensor or electrical / BUS rather than the uber expensive metal gearbox out repairs.

Most of the A604 shifting issues are a clogged solenoid pack. Because you have had the filter & magnet out I assume you had the NEG terminal off for at least 15 minutes - did you ?. The bottom line is you really can't afford not to have the transmission read properly before spending any more money otherwise you would be back to parts darts my friend. Many small indi's will have a capable reader for your year vehicle at about £35 a pop but you will have to ring round and ask :

- chrysler
- year
- 41TE

Hi QinteQ……..and thanks for the info………you’re so right about the 41TE being from the ‘Dark Arts Department’ lol

Followed the advice and spent much of yesterday contacting Transmission specialists, being referred here and there by outfits who were either unwilling to perform ‘code only’ diagnostics or regard such an old vehicle as offering little by way of reward😞. Still others ‘claimed’ they had no equipment to communicate with the TCM and then there were those seeking to charge at or near to dealer rates.😥

To tell the truth, I was becoming a little disheartened when I was referred to a small Liverpool based independent who were willing to do a code diagnostic for £40.00😊.

Got the car back this morning from the chap who has been conducting the investigative work on it (he is going away for 5 days) and the bad news is I tried the manual shift to 3rd and it makes no difference😭. Not sure what the earlier experience was all about, perhaps Limp Mode was not fully engaged or just an anomaly 😢?? ….Or perhaps just my wishful thinking😱…..

Took the car to Liverpool where the technician connected to their ‘Snap On’ Unit. After some initial difficulty establishing communications, only the code P0733 (Incorrect Ratio 3rd Gear) was recovered. The technician then tried their Bosch diagnostics kit but could not establish any connection at all. He is unsure whether the code was recovered from the PCM or from the TCM as no further diagnostic access was possible.

I have been asked to return on Monday when the boss (their Autos expert) is in, so they can have another try as I would have liked the CVI figures so as to offer at least some idea of the internal wear on the clutches. No charge until then…..

All in all this does not look promising as this code points to internal failure😂.

Any suggestions you can offer in respect of TCM data required and comms access for when I return on Monday?

Regards,

Voyager Pilot

The only avenue open to the likes of us re. autoboxes is to ensure the ATF is good. If it smells burnt, or if you know positively it is very old, new fluid is indicated, but needs a cash outlay of course with no guarantee of success.
However I seem to remember a poster on here finding chafed databus wiring causing an autobox fault. Might be worth trying to find it so you could at least examine your own wiring.

Leedsman.

Re the code you mention


Start by inspecting the transmission fluid level and condition, and change fluid if necessary.





You really need Richard (tfb) to sort this out. If you think about it, it's likely to be a sensor providing inaccurate information to the ECM, or dirty fluid or bad 3rd Solenoid. If you are sure the fluid is OK (does it smell burned? How many miles on it?) then it is more likely to be electrical than mechanical - unless the fluid is really bad blocking some galaries.


Sorry I cant be much help

Recurring Limp Mode
 

Hi again Leedsman/QinteQ/vrc883

Sorry for the excessive delay in posting my reply to your posts. Car has been forced to take a back seat just now (sadly funds are lacking and finding someone to work outside at this time of year is proving impossible just now :().

I did however wish to update with what progress (lack of) made thus far and to share my further research for the benefit of other forum members working with the same issue.

As indicated in my last post, I did return with the car to the transmission specialist on the Monday sadly to be informed that their equipment WOULD NOT after all hook up to the TCM of a 2000 and that the P0733 code would simply be a PCM code!

Their recommended course of action? Fit a reconditioned (fully guaranteed) box at a price of £2,000! On hearing that that was beyond my budget, repair was then discussed but with prices starting from the £600.00 + mark.....also beyond my budget!! I was referred on to the local (former) Chrysler main dealer who still have the Chrysler diagnostic kit for a code read before they would proceed as I was informed that this would be what they would do before commencing any repair. He did tell me they were very helpful and that the diagnostics would only take around 10 minutes to complete and did not charge me for the earlier code read.

I was a previous customer of this dealer when they were under the Chrysler flag and as it is located just 2 miles away it seemed sensible to pay them a visit whilst the vehicle was in the city so as to minimise any unnecessary mileage in limp mode. Regrettably on hearing the age of the vehicle they became singularly unhelpful to my predicament and despite technicians clearly available insisted that the vehicle must be booked in for an entire day with a minimum labour charge of 1.5 hours. Not wishing to put further wear on the transaxle for so little gain I declined their offer to book it in.

Brief research into the 'Scrappy' option followed finding suitable units available at around £700 - £800.... which I find hard to believe given no significant guarantee to their condition......

Returning to the 41TE fitted in the 98 I thought it prudent (whilst not able to do anything else on either vehicle:() to expand my research. So in a spirit of helping others seeking to accomplish this task I will share my research and of course invite comments from the experts here in respect of its accuracy.

Interchangability:

My attention has been drawn to the differences between the autotransaxle units installed through the model years most notably revisions to the Transmission Range Sensor and the final drive ratio's.

TCM:

Issues relating to the Pinion Factor (the 'LX' GS was equipped with 16" Tyres whilst the 'LE''s were 15") are apparently addressed by reprogramming the TCM with a suitable diagnostic tool using a menu selection for the correct Tyre size. Failure to do this will result in incorrect speedometer and odometer readings. This is therefore only necessary if the TCM (and/or smaller/larger wheels) are exchanged from another vehicle. To maintain electrical compatibility however a 2000 vehicle MUST have a 2000 TCM with the same primary OEM Part Number (in this case 04686952) subsequent part revisions 04686952AA through 04686952AF or later? are all fully compatible as I understand.....thoughts anyone?

Transaxle Units:

Many transaxle unit variants were installed to Gen 3 & Gen 4 Voyagers/Grand Voyagers between 1996 and 2005 interchangability is seemingly governed by several major factors:

1. Physical design of the Bell Housing (to mate with the crankcase) - This is specific to the engine size (i.e. a 3.0L Bell Housing WILL NOT fit a 3.3L engine).
2. Attachment holes/bolts - However I understand that Gen 4 housings whilst having extra attachment points will still mate suitably with these unused).
3. Flex Plate - 96 & 97's have one "D" shaped hole which requires 'rounding' to accommodate more recent transaxles.
4. Modules/Sensors - The Transmission Range Sensor has undergone 3 revisions and both their physical dimensions and connectors have changed.
5. Transmission Oil Tube/Dipstick - These differ between the Gen 3 and Gen 4 units but can be swapped over.
6. Final Drive Ratio - I understand this differs for each engine size but the 3.3L is always at 2.49. Given 1. above this should not be an issue ....again thoughts anyone?

In drawing these conclusions I found the following information/articles of immense value and draw all credit to the expert authors concerned.

Differences between transaxle unit part numbers and production years - the ATSG 41TE Update Handbook (available to download from here: http://usavans.ru/forum/download/file.php?id=24344) shows and explains all changes and revisions for each production year and all OEM Part Nos.

Differences between the revisions of the TRS "the Chrysler 41TE Transmission Range Sensor" in depth Sonnax article by Mike Steen here: Chrysler 41TE & 42LE Range Sensors - Sonnax NB. Article comprehensively discusses the revisions and their differences and shows how to circumvent the issue of interchangability with OEM Adapter Harnesses and Adapter Seal with images and part numbers.

General practical information on interchangability from a Chrysler Minivan Club Forum post by 'Working Plymouth' found here: Transmission Interchange Information For 3rd Generation

Useful OEM 41TE Part Numbers from the 'Transmission Rebuilders Network' here: TRNW - Transmission Rebuilders Network Worldwide: Membership Tour

History of the TRS changes during the '99 Model Year and the adapter harness developed - TSB 21-04-99 "Service And Parts Information On 1999 Running Changes To Transmission Range Sensor (TRS)" found here: http://robskorner.info/faqs/TSB/21-04-39.pdf

So to summarise, in regard to my issues the '98 donor should provide a straight swap provided that I can source an adapter harness to circumvent the revised TRS connector which is of the 'blade ' type on the 2000 and 'pin' type on the '98. The options are: 1. the OEM part 4868295AA (very expensive!) 2. An 'after market ' equivalent (eg. A604 Adapter Harness - MLPS) or 3. Lucky Scrap Yard find on an 'early' '99 with a old style TRS.

In investigating the harness I have also come across a number of examples of the 'Miller' Transmission Simulator Harness (Part No 8333-12 Miller Tools Trans Range Sensor Harness 8333 12A | eBay) which appears to be identical and available at a lower cost. Can anybody comment as to whether these are simple "connector to connector" convertor harnesses and therefore suitable or else have some internal component to facilitate connection with the test equipment?

Alternately, if anyone has a good example available and would like to PM me I will happily sort via PayPal......

Hope the above info is of help to other board members!!

Voyager Pilot