Connecting fault output device V.A.G 1551 and selecting function — VW

Note:

The vehicle system tester V.A.G 1552 cannot be used instead of the fault output device V.A.G 1551.

Open up cover of the diagnosis plug -1-.
Connect fault output device with the cable V.A.G 1551/5
-2- to the diagnosis connection.

Once the fault output device is connected:

Connect exhaust gas extraction hose to the heater unit exhaust pipe.

Switch on heater unit.

The diode -0- lights up on the diagnostic cable
V.A.G 1551/5.

LT DIAGNOSIS
HELP
Enter address word XX
Readout on display:

Note:

If the readouts shown in the procedure are not achieved on the display:

=> Operating instructions for fault readout device

If "faults in data interchange" is displayed as a result of typing errors, disconnect cable on fault output, reconnect and carry out the work steps again.
Depending on the program, additional operating instructions can be printed out via the HELP key of V.A.G 1551.
The ⇒ key is used to advance the program sequence.
The PRINT key is used to switch on the printer (the indicator lamp in the key lights up).

A list of selectable heater control units is printed out on the V.A.G 1551 printer after the HELP key is pressed.

LT address words
01 · Diesel control
25 · Immobiliser
81 · Engine control
82 · ABS
83 · Tachograph
84 · Auxiliary heater
87 · Airbag/emergency tensioning retractors
89 · Instrument cluster

Press keys -8- and -4- (the address word of the "Auxiliary heater" vehicle system to be tested is entered with 8 and 4).

The diode -4- lights up on the diagnostic cable V.A.G 1551/5.

LT DIAGNOSIS
Q
84 - Auxiliary heater
Readout on display:

Acknowledge the input with the Q key.

LT DIAGNOSIS
HELP
Please wait . . .
Readout on display:

and the following display appears, for example:

The heater control unit identification number is displayed:

000 VVW 09 29
ZHE
04
⇒
Readout on display:

Press the ⇒key.

HELP
The control module does not answer
The message opposite appears again on the display of the fault output device V.A.G 1551

Disconnect fault output device V.A.G 1551 from the diagnosis connection and reconnect.
Switch on heater unit.
Repeat function selection => from page
01-7
, connect fault output device V.A.G 1551 and select function.

HELP
The control module does not answer
The message opposite appears again on the display of the fault output device V.A.G 1551

Press HELP key on fault output device V.A.G 1551.

A list of possible causes is printed out on the V.A.G 1551 printer after the HELP key is pressed.

Rectify cause of the fault.
Repeat function selection => from page
01-7
, connect fault output device V.A.G 1551 and select function.

LT DIAGNOSIS
HELP
Select function XX
Readout on display

A list of selectable functions is printed out on the V.A.G 1551 printer after the HELP key is pressed.

Overview of functions
011) · Interrogate heater control unit version
021) · Interrogate fault memory
03 · Actuator diagnosis
04 · Basic adjustment
051) · Erasing fault memory
061) · Finish diagnosis
08 · Read measured data block

1)
Only these functions can be performed at the moment.