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Discussion Starter #1
Hey All,

Wife was heading to work the other day and got stuck on the road car won't move, idles fine, gears box shift got P0700 code had it towed to home and now sitting on the driveway.

My plan of action once the weather starts getting warmer.

1st. Try the quick solution replace the Transmission Adapter Plug (since I have a spare one from the first time this happened back in 2013.)
2nd. Drop the pan and replace the conductor plate since this was the issue that happened in 2013.

I think this is a straight forward solution my only questions are:

1. How do I get new transmission fluid back into the case after I put the pan back on?
2. Anyone came up with an alternative to the Transmission Dip Stick, I found one for $30.00 on Amazon, rather not buy this since don't see too much future usage.
3. Should I do the transmission mount while I am down there? Car is 1997 with 116K.
4. Any suggestion on where to get the conductor plate from?

Thanks Pin2
 

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The P0700 code is generic and the cause can be one or more of many things. If you have an access to a scanner that can read the codes from the TCM to identify what the 3 digit code or codes are that somewhat help you pin-point the root cause.

Is the car in electrical limp mode (meaning the car starts and goes forward and backward but at a set gear (usually second) ?

Or is the car in mechanical limp mode (the car starts and goes for a while then gets stuck to a gear (or transmission starts slipping) till you stop and restart the car ?

Or the car does not move at all with gear shifted to D or R?

You can do all those things you listed but this will not guarantee that it will fix your problem.
 

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Discussion Starter #4
Thanks Mr. Boca.

At at first the car moved after sitting for 2 days when I put it in D and R. Than when I tried again it does nothing in either D or R looks like the transmission is not engageing. Based on your feedback looks like Mechanical Limp Mode.

Here is a link to a video I took.

https://app.box.com/s/b1ivmetrbj8v0deac1k3o7gszqtbpzso

Thanks.




The P0700 code is generic and the cause can be one or more of many things. If you have an access to a scanner that can read the codes from the TCM to identify what the 3 digit code or codes are that somewhat help you pin-point the root cause.

Is the car in electrical limp mode (meaning the car starts and goes forward and backward but at a set gear (usually second) ?

Or is the car in mechanical limp mode (the car starts and goes for a while then gets stuck to a gear (or transmission starts slipping) till you stop and restart the car ?

Or the car does not move at all with gear shifted to D or R?

You can do all those things you listed but this will not guarantee that it will fix your problem.
 

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Can't access the video. Can you upload it to youtube ?

From what you are describing, it seems to be an issue with the rpm sensors on the conductor plate. This could be a conductor plate issue, or the trans connector adapter / TCM contamination issue. Again detailed codes from the TCM will help more.

You can replace the adapter and check the TCM out for contamination. If you are lucky, you will not have to reset the TCM which would require special diagnostic scanner that can read and reset TCM codes.
 

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No, mechanical limp mode = 2nd gear all the time. Every time you shift to R or D, it should feel like a very harsh clunk. That's mechanical limp mode. You can still move the car, even if the TCM is unplugged or pilot bushing out.

No moving while in R or D....that's different.
 

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Discussion Starter #7
Thanks here is the youtube link.

I checked the TCM module it didn't have any ATF contamination. I will check the trans adapter connector tomorrow.😊

Where can I get the code reader that you are referring to for TCM code?

Pin2


Can't access the video. Can you upload it to youtube ?

From what you are describing, it seems to be an issue with the rpm sensors on the conductor plate. This could be a conductor plate issue, or the trans connector adapter / TCM contamination issue. Again detailed codes from the TCM will help more.

You can replace the adapter and check the TCM out for contamination. If you are lucky, you will not have to reset the TCM which would require special diagnostic scanner that can read and reset TCM codes.
 

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Have a look at the link below for P0700. You will see multiple appearances with different symptoms. Have a look at the code 015 / 111 / P0700 which seems to describe your symptoms provided that this is the only fault present.

"Transmission does not transmit engine power." Is that what you are experiencing ?

STAR TekInfo

As you can see there are host of other reasons for P0700 combined with other codes. The scanner you need can read the 3 digit TCM codes like 015 / 111 from the TCM, and can also reset them which you may have to do.


Diagnostic equipment like Snap On, Autel, MB DAS, Delphi, CarSoft etc. can access the TCM using their specific 38-pin diagnostic adapters. These are not cheap and takes time to learn for some of them. Easiest way is to find someone who has them, or have the car scanned at a repair shop that has the right equipment (at a price of course).
 

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Well, damn. Today I learn a few things.

Harness is damaged from ETC control module to each RPM sensor.
RPM sensors are faulty.
Hmmm, that does sound like the speed sensor on the conductor plate....that's much more common than a damaged ETC harness....unless OP has a mouse/rat/squirrel infestation.
 

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Definitely sounds like a conductor plate issue, specifically y3/6n3. This seems to be, along with the starter lockout contact; the 2 things that cause failure on the conductor plate.

A scan is your first move though. You will be glad.


Sent from my iPhone using Tapatalk
 

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Discussion Starter #11
I was finally able to get under the car and get a visual of the external. Don't know why there is all this oil but might be residual oil from the engine.



 

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Discussion Starter #12
Wanted to give an update, I was able to get the Foxwell Scanner from Amazon and yesterday I tried the scan.

1. The scanner didn't pick up any codes both using the OBD and Data Link ports for scanning.
2. I tried the transmission only scan and it give me "communication error need to connect to..."

Does this mean the TCM is bad? Right now there is zero activity when I turn the car on and put the car into gear. I mean sound of shifting, not feeling of transmission movement, the clunk noise when the gear shiftier is moved.

The engine turns, warms up and in the beginning you can tell the starter is spinning with the "whinnding" noise before it slows down.

Any thoughts?
 

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Hello:)

What Foxwell scanner did you use and what adapter did you use to connect to the 38 pin connector ? Does the scanner pick up ANY OTHER module at all (ECM, SRS, ABS etc)?


Make sure that the Transmission module is powered when the ignition key is in the run (position 2) location. It is the red/yellow colored wire that comes out of the K40 relay.
 

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Discussion Starter #14
Mrboca,

I have the Foxwell NT510 scanner which has the Mercedez SW installed https://www.amazon.com/gp/product/B07BQH1S5X/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1. I figured out what my problem might be I am using a straight OBD to 38-pin cable which is only passive. Looks like I need a special 38-pin cable to do the actual scan looking at getting it from Foxwell Foxwell Benz 38 pin and Extension Cable for Foxwell NT510 NT520 PRO Multi-System Scannerbut might be 2 weeks for delivery.

BTW, last week I did unplug the TCU to check for ATF build up, but I never disengaged the battery before doing so would this cause the TCU needing to be reset?

Also to answer your other question YES the scanner DOES pick up other module stats (ECM, A/C, SRS, ABS, and can view live data like coolant temp. etc...)

I did notice the RPM live data was fluctuating which correlates to the RPN gauge being flaky.

This is a learning curve for me so appreciate your feedback.


Hello:)

What Foxwell scanner did you use and what adapter did you use to connect to the 38 pin connector? Does the scanner pick up ANY OTHER module at all (ECM, SRS, ABS etc)?


Make sure that the Transmission module is powered when the ignition key is in the run (position 2) location. It is the red/yellow colored wire that comes out of the K40 relay.
 

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Yeah , that is the right adapter and the extension that needs to be used. When you connect the scanner to the OBD2 or to the 38 pin "generic" cable with 3 wires, you can only access, the ECM fault codes AND the ECM data. The ECM real time data has valuable information (as reported or broadcast over the CAN bus) from the other modules, but you cannot access the other modules to read their specific information and fault codes, and you cannot reset them.

When you use the specific cable adapter, the multiplexer inside the in-line box allows the scanner to access individual pins of the 38 pin diagnostic port.

Once you get the adapter, the codes from the transmission module will reveal the issue a bit more. At least you can clear the code(s) and see if it allows you shift gears.
 

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Discussion Starter #16 (Edited)
Finally was able to scan.

Update:

1) Did a scan with the car running and warmed up with the right cable for the Foxwell scanner and was able to pull 9 codes from the transmission scan.

The codes are:

  1. 114
  2. 116
  3. 120
  4. 121
  5. 135
  6. 65
  7. 132
  8. 147
  9. 161
2) I reset the codes and did another scan and it was clear no new codes.

3) Try to drive the car from the driveway into the garage since it was towed only to the driveway car was not moving.

4) I followed the procedure to "relearn" the transmission and restarted the car, it was able to shift and I was able to drive about 20 feet into my garage. Than it would not engage when I tried other gears. The car felt like it was back the way its been for past week not moving.

5) I did another scan and no new codes all was clear but got Lamp Defective error (the left daylight driving bulb went.)

6) I followed the procedure to "relearn" the transmission and restarted the car, it was able to shift and I could feel the transmission engaging when I shifted into different gears.

7) Again I was able to move about a foot and again car went into same behavior that it had been for past week, transmission not engaging.

Any thoughts what path I should take to fix this.

Here is the video of the scan:


Pintu:frown
 

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Start the car several times and shift gears, and then scan the TCM and ECM (the engine computer). If there are still no fault codes, I believe it is something mechanical (oil pump, valve body issues), or hydraulic (not enough ATF, clogged / dislocated ATF filter). I do not know what the Relearn process changes in the TCM, apart from resetting some of the parameters in the TCM.

You need to invest in a dipstick (you can get one for $15) and measure the ATF level when the ignition is OFF, and then start the engine and shift gears several times, and check the fluid level if it drops at all.

I would also order some spec. ATF and a genuine ATF filter and a pan gasket.

Does your scanner allow you to look at the status of the shift solenoids, rpm sensors ?

If you have no faults reported by the TCM / ECM, it is very likely that there are no electrical issues associated with the conductor plate / adapter / TCM.
 

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Discussion Starter #18
I have a strong feeling that the issue is with the ATF, I know my wife was complaining about lack of power and delay response from acceleration.

Going to do the change this weekend and see where I go after that.

I did order the dipstick so that will help also.

Here is the picture of the homemade dip stick not to easy to ready but its something. This was at cold reading it was a little above the mark but will try again with the OEM dip stick.

I think the scanner does allow live stats will looking into that once I get home today after work.

Thanks again.
 

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Don't forget to order the OEM ATF filter. Some of the after-market filters have proper fitment issues. Make sure the old filter comes out with its o-ring.

The ATF color seems to be a bit yellowish. Probably the lighting issue. With the home-made dipstick, you cannot be sure whether the tip goes all the way down through the neck stop.
 

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Discussion Starter #20
I always us Mann filter for everything is that the OEM?

Don't forget to order the OEM ATF filter. Some of the after-market filters have proper fitment issues. Make sure the old filter comes out with its o-ring.

The ATF color seems to be a bit yellowish. Probably the lighting issue. With the home-made dipstick, you cannot be sure whether the tip goes all the way down through the neck stop.
 
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