Error Code P0726 in Auto Transmission Module

First of all I am very new to Ross Tech, thinking of buying one. Last week, my car Q5 2.0TFSI with 0B5 S tronic gearbox showed 'Gearbox Malfunction You can continue driving", so I scanned my car with typical OBD2 scanner. There's an error P0726 displaying. I googled up this code and found that it's RPM signal. I'm wondering if I buy VCDS cable, will I be able to examine what causes the problem. I don't want to pay for the new mechatronic module, which is really expensive. I heard about Software update to gearbox, will VCDS will able to do that? I think I have DMF failure, will VCDS be able to report DMF failure? Thank you

Welcome to the forum.

First job is register your VCDS cable online VCDS Dongle Registration. Then you'll get more response from users.

Second job is if you have a problem/query you ALWAYS post a full AutoScan of the vehicle in question, whether there are any error codes or not. There is more useful system info in there. How to post an Auto-Scan

There is nothing in VCDS Wiki about this code only http://wiki.ross-tech.com/wiki/index.php/18148/P1740/005952

What I have is:

VAG Error Code: 17110/10657
EOBD II Error Code: P0726

Fault Location:
Engine Speed Input Circuit from Engine Control Module (ECM) - Range/Performance Problem/Upper Limit Exceeded/Implausible Signal

Possible Cause:
Malfunction Indicator Lamp (MIL)(K83) active.

Wiring/Connector(s).
Crankshaft Position (CKP) Sensor.
Communication error between the Engine Control Module (ECM) and Transmission Control Module (TCM) (J217).

When is the code detected?:
The P0726 Codes is triggered when the Transmission Control Module (TCM) detected that the calculated engine speed is greater than the RPM's received from Engine Control Module (ECM).

Description:
The Engine Control Module (ECM) monitors the engine speed through the Crankshaft Position (CKP) sensor with the engine running, and send signal to the Transmission Control Module (TCM).

As taken from my app.

vdubz said:

First of all I am very new to Ross Tech, thinking of buying one. Last week, my car Q5 2.0TFSI with 0B5 S tronic gearbox showed 'Gearbox Malfunction You can continue driving", so I scanned my car with typical OBD2 scanner. There's an error P0726 displaying. I googled up this code and found that it's RPM signal. I'm wondering if I buy VCDS cable, will I be able to examine what causes the problem. I don't want to pay for the new mechatronic module, which is really expensive. I heard about Software update to gearbox, will VCDS will able to do that? I think I have DMF failure, will VCDS be able to report DMF failure? Thank you

Click to expand...

VCDS can certainly get you more a lot more data than a generic OBD-II scanner, but it cannot do software updates to control modules.

What is DMF?

-Uwe-

Keithuk said:

Welcome to the forum.

First job is register your VCDS cable online VCDS Dongle Registration. Then you'll get more response from users.

Second job is if you have a problem/query you ALWAYS post a full AutoScan of the vehicle in question, whether there are any error codes or not. There is more useful system info in there. How to post an Auto-Scan

Click to expand...

Your advice is a bit premature. This is the Pre-Sales Support section of the forum and the OP clearly stated he is "thinking of buying one".

-Uwe-

Uwe said:

What is DMF?

-Uwe-

Click to expand...

Dual Mass Flywheel (DMF).

If he's thinking of buying where as he had the P0726 code from?

I just like to get the ball rolling with new users.

Keithuk said:

Dual Mass Flywheel (DMF).

Click to expand...

Added to the acronym decoder, thanks.

Do cars with automatic transmissions use dual mass flywheels?

-Uwe-

Yes I believe they do.

Keithuk said:

Dual Mass Flywheel (DMF).

If he's thinking of buying where as he had the P0726 code from?

I just like to get the ball rolling with new users.

Click to expand...

from a generic obd2 scanner. Since that you mentioned that you got the information from your app, is it from RossTech app?

Uwe said:

VCDS can certainly get you more a lot more data than a generic OBD-II scanner, but it cannot do software updates to control modules.

What is DMF?

-Uwe-

Click to expand...

DMF = Dual Mass Flywheel. According to Keithuk, P0726 is triggered when the Transmission Control Module (TCM) detected that the calculated engine speed is greater than the RPM's received from Engine Control Module (ECM), I'm wondering if VCDS is able to determine whether TCM calculated the engine speed incorrectly or ECM calculated engine speed incorrectly. I believe that TCM and ECM are quite pricey, don't want to place both to solve my problem. Better invest in HEXnet and replace just faulty item. Cheers