Limp mode

[dco]

My 01 NB with 01m transmission seems to be in limp mode. The cel comes on and my generic obd reader gives me a p0700 code. The car seems to be in 3rd gear all the time. When I clear the code the car shifts normally. The code has come back. After searching this great site I am thinking one of my speed sensors is bad. I am assuming it is not the vehicle speed sensor since my speedometer is having no issues. Should I just go ahead and replace the other two sensors? Not sure how hard they are to get to. Any advice would be greatly appreciated.

[Smileybug]

The code you are getting is for "Transm.Contr.System Malfunction". My usual go-to on code descriptions is failing me today on this one. Doesn't sound like a speed sensor though. My thought goes to possibly valve body, but I don't know autos at all.

[IndyTom]

I found this answer about the Code online. Answered by a Certified VW Mechanic:

P0700 Code:

This means that there is a fault within the electrical part of the transmission. To find out what the fault code is for the transmission, will require you to have the transmission control unit scanned. This can only be done with someone with a factory type scanner or a transmission shop. There are too many items that can set this fault code, so without guessing it needs to be scanned. A generic OBDII scanner will not read transmission fault codes.

Read more: 2002 vw beetle desiel turbo. My beetle has code p0700 (mil - JustAnswer 2002 vw beetle desiel turbo. My beetle has code p0700 (mil - JustAnswer

[dco]

I didn't think it would be the valve body since the shifting (after the code is cleared) is smooth. It took about 15 miles for the light to come on last time. I have driven it nearly 60 miles today, including some highway driving at 75 mph and still no light. I'm sure it will come on again. I have only owned the car for a month and I have done the TB,WP, tensioner, third brake light, and hazard/turn signal relay! Maybe the transmission is just getting used to a younger driver as my mother probably never got it over 55 mph

[Smileybug]

The VW autos are known for failures. Especially after 100k. Don't think its "getting used to your driving". If the light is coming on, there is a problem.

[Blugg]

Originally Posted by dco

I didn't think it would be the valve body since the shifting (after the code is cleared) is smooth. It took about 15 miles for the light to come on last time. I have driven it nearly 60 miles today, including some highway driving at 75 mph and still no light. I'm sure it will come on again. I have only owned the car for a month and I have done the TB,WP, tensioner, third brake light, and hazard/turn signal relay! Maybe the transmission is just getting used to a younger driver as my mother probably never got it over 55 mph

Not a reply to your fault.

But when my engine check light was on, i used to reset it. Then it would take a day to a month before coming back on. By the time i stuck it in the garage, 2 sensors had gone and a few other things. When the codes were read by the garage, i'd made things worse by just ignoring it and reseting the light

Try and get a mechanic to look at it, before it escalates like mine did.

[dco]

I've been driving the car to work for the past week. A few times it started the day in limp mode. After shutting the car off and turning it back on it shifted fine. I bought a 3rd party interface off of ebay and downloaded vcds lite shareware and tested it today (the cel came on yesterday, first time since last week after about 200 miles). VCDS gave me a code that read 65535 Internal Control Module Memory Error. Anyone have any ideas what the problem may be? Thanks for any replies.

[IndyTom]

Originally Posted by dco

I've been driving the car to work for the past week. A few times it started the day in limp mode. After shutting the car off and turning it back on it shifted fine. I bought a 3rd party interface off of ebay and downloaded vcds lite shareware and tested it today (the cel came on yesterday, first time since last week after about 200 miles). VCDS gave me a code that read 65535 Internal Control Module Memory Error. Anyone have any ideas what the problem may be? Thanks for any replies.

This is what I found at Ross Tech Wiki:


Internal Control Module Memory Error

Possible Causes
Wiring from/to Control Module faulty
Voltage Supply and/or Ground Supply faulty

Control Module faulty Control Module Housing leaky

Possible Solutions
Check/Clean Wiring from/to Control Module
Check Voltage Supply and Ground Supply including the Main Supply/Connections at the Battery

Replace Control Module

Special Notes
This fault is NOT to be ignored when found in a major and/or critical system (Airbag, ABS etc.).
When stored in other unimportant systems (Radio etc.) the general suggestion is to ignore it unless you notice functional limitations. Within the warranty period dealers are usually required to replace such control modules, but there have been a couple of cases with similar codes where these are getting ignored due to flaws in the control module software. If in doubt please refer to technical bulletins and similar documents provided by the vehicle manufacturer.
Audi Airbag 6 & 7 Problem: A fault of the acceleration sensor may result in the above fault.
Solution: Replace Airbag control module and both acceleration sensors.

Audi Airbag 8 Problem: Due to under voltage the control module does not complete it's self test successfully.
Solution: Replace Airbag control module and install a under voltage protection relay for it.

Certain older TDI ECUs which have a vacuum line going to them Problem: Vacuum line broken, either before ECU or inside ECU.
Solution: Inspect and repair vacuum lines to ECU and inside ECU.


65535 - Ross-Tech Wiki

[dco]

Thanks for the reply. I'm not sure what to make of this. I am no VW mechanic. Don't know where the internal control module is or anything about it. How does this relate to the P0700 code my OBD II scanner is giving me? It looks like this thing may be dealer bound if I can't try something myself.

[IndyTom]

Originally Posted by dco

Thanks for the reply. I'm not sure what to make of this. I am no VW mechanic. Don't know where the internal control module is or anything about it. How does this relate to the P0700 code my OBD II scanner is giving me? It looks like this thing may be dealer bound if I can't try something myself.

The ECM or computer of you beetle is located under the drivers side dash cover. To get to it you will need to take the center piece off (it slides back and then up and forward), then the drivers side piece comes off and then there is another metal cover that needs to be unbolted. Under there is where you can find the ECM or Electronic Control Module. There are two main cables going into the ECM. They should be locked in place but I suppose it is possible that one of them perhaps gotten loose somehow. Wouldn't hurt to check. MORAV has a Bentley, perhaps he or someone can post a diagram on how to access the ECM more in detail.
The P0700 code is pretty general and usually means an issue with the TCM - Transmission Control Unit which the ECM and TCM are combined in the Beetle. So it still points either to a cable going into the ECM/TCM control unit or it is a faulty Computer control unit. They do go out on occasion and I am sure the dealer will want to replace this unit if you bring it to them. I have seen them run between 90 to 160 bucks. But I am sure the dealer will charge you plenty more than that plus their rediculous labor costs. Shouldn't be more than a 45 minute job to replace the ECM but I am sure the dealer charges at least 2 hours to do it.

[dco]

Thanks again. If this is what we are talking about 01 VW BEETLE ENGINE COMPUTER ECU ECM | eBay

I may be able to swap it out if it is just plugging in the wires and such. There seem to be many on ebay.

[IndyTom]

Originally Posted by dco

Thanks again. If this is what we are talking about 01 VW BEETLE ENGINE COMPUTER ECU ECM | eBay

I may be able to swap it out if it is just plugging in the wires and such. There seem to be many on ebay.

That one is for a 2001 with Manual Transmission. If you do get one make sure it's the right kind. Another issue is that when you do swap it out the dealer may need to reprogram your keys because the imobilizer function may not recognize the new ECU.

[dco]

A new dealership opened up just a few minutes from my house so I took my nb in for the problem. They said it is the TCM. $1200 quote for putting in a new one. I asked about used/refurb. ones and they checked on it and called back and told me they could get one for $300 (new ones were $900). Total bill for installing a used one will be between $500-$600. 90 day warranty on the used TCM. I'm going with the used one and see what happens. Thought about buying one myself and changing it but than I would still have to bring it to the dealership to get it set up with the imobilizer. I'm hoping this isn't too bad of a ripoff. Thanks for all the replies and advice.

[IndyTom]

Originally Posted by dco

A new dealership opened up just a few minutes from my house so I took my nb in for the problem. They said it is the TCM. $1200 quote for putting in a new one. I asked about used/refurb. ones and they checked on it and called back and told me they could get one for $300 (new ones were $900). Total bill for installing a used one will be between $500-$600. 90 day warranty on the used TCM. I'm going with the used one and see what happens. Thought about buying one myself and changing it but than I would still have to bring it to the dealership to get it set up with the imobilizer. I'm hoping this isn't too bad of a ripoff. Thanks for all the replies and advice.

WOW, that is a bit HIGH especially for a used ECM/TCM unit.
Putting it in takes about 30 minutes to 45 minutes. When I took my ECM out it took me about 30 Minutes the first time.
Putting it back in wasn't too bad. I just broke one of the clips holding it in. They are cheap plastic and they break very quickly. No biggie, Zip ties work a lot better and are more secure than those cheap clips VW uses. So they charge 300 bucks for the part and 300 Labor for less than an hour work. Hmm, sounds about right for a VW Dealership.

[dco]

Well my Beetle spent almost 2 weeks at the dealership trying to get this TCM problem straight. They got a faulty TCM first, the wrong TCM next and another faulty one after that. They finally located one in Florida that checked out good and had it shipped. It took a few days (since it was over the Christmas holiday), and when it arrived, they told me they sent the ECU instead of the TCM. They had them overnight the TCM and had it the next day. Since my car was there for so long they didn't charge me any labor for this job. I had them do a transmission fluid and filter while the car was there. They charged me $250 for that (another dealer quoted me $350). All in all I thought they treated me right by dropping $210 of labor charges. Got the TCM and a tranny fluid/filter change for $550. The car seems to be running fine now.

[IndyTom]

Originally Posted by dco

Well my Beetle spent almost 2 weeks at the dealership trying to get this TCM problem straight. They got a faulty TCM first, the wrong TCM next and another faulty one after that. They finally located one in Florida that checked out good and had it shipped. It took a few days (since it was over the Christmas holiday), and when it arrived, they told me they sent the ECU instead of the TCM. They had them overnight the TCM and had it the next day. Since my car was there for so long they didn't charge me any labor for this job. I had them do a transmission fluid and filter while the car was there. They charged me $250 for that (another dealer quoted me $350). All in all I thought they treated me right by dropping $210 of labor charges. Got the TCM and a tranny fluid/filter change for $550. The car seems to be running fine now.

Congrats! I am glad you got it all fixed!

Happy New Year!!!

[407pic]

I have been working on all the same issues. To date I have replaced all the transmission sensors, and had the Air Bag Module reprogrammed. I am down to the TCM or the ECU. p0700 then had a VW repair shop run scan and get the 65535 error. That lead to the reprogramming of the Air Bag Module. My question is if I have to replace the ECU does it have to be reprogrammed by the dealer.

[dco]

The dealer on replaced my TCM (not the ECU). No reprogramming was needed except resetting the transmission which I believe is done by holding down the accelerator pedal for a short time with the key in the on position (or something similar to this). One thing to keep in mind though is the TCM must be an exact match as I'm guessing there are a few models out there for each engine.