Volkswagen Golf / Golf GTI / Jetta. Manual — part 374

01-172

Output Diagnosic Test Mode (DTM)

Note:

All functions which could previously be

performed with V.A.G 1551 can now also be
carried out with the tester VAS 5051.

The pump motor and the correct functioning of

the hydraulic circuits (allocation of brake lines to
wheel cylinders and function of valves) can be
checked via the output DTM for interchange or
leaks.

The vehicle must be raised until all wheels are

free to turn. (2nd mechanic required to rotate
wheels)

The -C- key can be used to exit the test

sequence at any time.

After depressing the brake pedal several times

the vacuum in the brake booster will be
exhausted. Therefore more pressure must be
applied to the brake pedal in order to attain the
same fluid pressure in brake system, as that
attained with vacuum.

When vacuum in brake booster is exhausted it

can happen that the wheels do not lock; start
engine and build-up vacuum in brake booster.

On Board Diagnostic (OBD), performing

01-173

Example:

Indicated on V.A.G 1551 display during

Output DTM:

(e.g. front left wheel, FL)

Output Diagnosic Test Mode -

IFL: VBAT OFL: 0V Wheel FL locked

IFL = Inlet valve Front Left

VBAT = Voltage Battery; Voltage at valve

OFL = Outlet valve Front Left

0V = 0 Volt; No voltage at valve

Locked/free = Wheel condition; must be

checked by 2nd mechanic if required

Output Diagnosic Test Mode -

EDL valves/Hyd-P: VBAT Wheel FL/FR
locked

Hydr-P = Hydraulic pump

On Board Diagnostic (OBD), performing

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- Connect V.A.G 1551 scan tool.

- Switch on ignition.

- Press key -1- for "Rapid data transfer" operating

mode.

- Select brake electronics control module

(address word 03);

Page 01-165

.

Rapid data transfer

Q

03 - Brake electronics

Indicated on display:

Note:

During the next work steps the ABS warning light -
K47- flashes.

- Confirm entry with key Q.

- Read off control module version in V.A.G 1551

display.

- Press

key.

On Board Diagnostic (OBD), performing

01-175

Rapid data transfer

HELP

Select function XX

Indicated on display

- Press keys 0 and 3

Rapid data transfer

Q

03 - Output Diagnosic Test Mode

Indicated on display

ABS hydraulic pump -V64- must
run.

- Confirm entry with key Q.

Output Diagnosic Test Mode

-

ABS hydraulic pump - V64

Indicated on display

- Press

key.

Output Diagnosic Test Mode

-

Operate brakes

Indicated on display

- Operate brake pedal.

- Press

key.

Output Diagnosic Test Mode

-

IFL: 0V OFL: 0V

Wheel FL locked

Indicated on display

Note:

If the wheel does not lock, there is a
possibility that there is a malfunction
in the mechanical/hydraulic part of
the brake system.

- Indicate to 2nd mechanic which

wheel requires turning by hand.

On Board Diagnostic (OBD), performing