Initial Inspection and Diagnostic Overview
Troubleshooting
=> [ Control Module Behavior when there is a Malfunction, information ]
=> [ Troubleshooting, Special Information ]
Before beginning any repair work, the cause of damage should be pinpointed using "Guided Fault Finding".
Perform Guided Fault Finding using the vehicle diagnosis, testing and information system (VAS 5051).
Control Module Behavior when there is a Malfunction, information
The control module works with developed software. This software has the ability to execute electrical functions, monitor and control within milliseconds. Everything modern transmission electronics have going for them is located in this control module. This should also be considered during troubleshooting.
However, no electronics can do what they were not designed to do. Likewise, it is not possible to detect electronically, for example, where the transmission housing is leaking and oil is escaping. However, it is possible to detect the effects of low oil. A failure in gear monitoring would be recognized causing the control module to respond that both clutches are open (no traction).
You should know this during troubleshooting and also when working with the tester. It is possible that the cause for the malfunction might not be found during Guided Fault Finding
In addition to updating the software, much has been done to protect the transmission should there be a malfunction (safety features). And so, when necessary, malfunctions are saved and a replacement program is started.
Control Module Behavior During a Malfunction
If a component in the transmission malfunctions, the control module reacts with a replacement function. In order to protect the transmission, there are 4 different kinds of malfunctions:
1. The malfunction is so minor that it is possible to continue driving with a replacement program while maintaining driving safety. The driver is not notified of this via the selector lever transmission range display (Y5). The display shows the selector lever position normally. When can changes in driving behavior actually be detected.
2. Individual lever positions blink in the selector lever transmission range display. The driver is shown that a desired gear selection is currently not possible. An example: Reverse, lever in "R" and vehicle drives backward. If "D" is engaged in this situation, the letter "D" blinks in the selector lever transmission range display. In this case, the control module prevents 1st gear from being engaged to avoid damaging the transmission. The gear is only engaged when the vehicle is stopped.
3. The selector lever transmission range display is completely lit up and blinks. The selector lever position is indicated. An example of this: Transmission oil temperature is too high. Reasons can be, among other things: Towing a trailer with too heavy of a load, installing accessories on front of the vehicle, lack of cooling air.
4. The selector lever position cannot be recognized. The selector lever transmission range display blinks. Differences in the driving and shifting can definitely be felt. It is not possible to shift into reverse. There is a serious malfunction, a sub-transmission is switched off, transmission repair is necessary.
Troubleshooting, Special Information
Selector Lever Position Display, No "R":
Simultaneous lighting of all segments of the transmission range selector lever display indicates the transmission is in emergency running mode. The vehicle does not drive in reverse.
Tip Function Malfunction, No Gear Selection:
Check the lock washers on the selector lever cable bracket at the top of the transmission. Washer - B - especially must never be used twice.
The lock washer - B - can get lost if it loses its residual stress. The - arrow - points to the cable adjustment bolt.
Drive Faulty - Insufficient Oil Suspected:
First, go to => [ DSG(R) Oil ] DSG(R) Oil.
Only add oil if you have definitely seen: oil is leaking. Under any other circumstances it is just a needless expense that does not help.
No Faults are Stored:
This especially depends on you. Experience shows that often a fault that is attributed to the transmission was caused by other components or units.
Poor shifting behavior is a result of insufficient engine air supply. Do not make mistakes like this.
If such faults are to be eliminated, you can work sensibly with the VW tester.
Faults are Stored:
Find out which faults have been stored. Volkswagen testers offer Guided Fault Finding. Using Guided Fault Finding can determine the cause of many malfunctions.
Malfunctions Outside the Transmission:
If, for example, there is a malfunction in the transmission: "ABS signal missing" is stored in the transmission and perhaps another control module also says: "ABS signal missing": Then do not continue to suspect the transmission control module is faulty.
The entry simply means: The transmission (and possibly other control modules) is waiting for a signal via the BUS but is not receiving it. In this case, the Anti-lock Brake System (ABS) has a problem. Under no circumstances should you remove the DSG transmission Mechatronic (J743). In this example, the fault points to problems with the ABS.