Work sequence

• Connect V.A.G 1551/1552 (Connecting scan tool and selecting engine electronics control module → Scan Tool V.A.G 1551 , connecting  .)
• Run engine at idle speed and press buttons - 0  - and - 1  - to select "Engine electronics" address word 01.

Indicated on display

• Press buttons - 0  - and - 8  - to select "Read measured value block" function 08 and confirm entry with - Q  - button.

Indicated on display

• Press buttons - 0  - , - 0  - and - 6  - to select "Display group number 6" and confirm entry with - Q  - button.
• Observe display in display field 2.

• Specification: x 0 0
• Center display = Brake pedal switch
• Right-hand display = Brake light switch

• Operate brake pedal slowly.

Both displays must change from 0 to 1 at same time.

• Specification: x 1 1

• Release brake pedal slowly into rest position again.

Both displays must change from 1 to 0 again.

• Specification: x 0 0

• Press → button.
• Press buttons - 0  - and - 6  - to select "End output" function 06 and confirm entry with - Q  - button.
• Turn off ignition.

If one or both displays do not change:

• Disconnect 4-pin connector from brake light switch and brake pedal switch.

Fig 1: 4-Pin Harness Connector & Terminals

Courtesy of VOLKSWAGEN UNITED STATES, INC.

• Measure resistance between terminals 1 + 4 of switch.

• Specification: Brake pedal not depressed: ∞ Ω;~Brake pedal depressed: max. 1.5 Ω

• Measure resistance between terminals 2 + 3 of switch.

• Specification: Brake pedal not depressed: max. 1.5 Ω; Brake pedal depressed: ∞ Ω

If specifications are not obtained:

• Replace Brake Light Switch F and Brake Pedal Switch F47.
• After replacing the switch, press the pedal 3 times to ensure the correct adjustment of the switch.
• Verify that the switch is working properly → Brake light switch and brake pedal switch, checking  .

If specifications are obtained:

• Remove wiper arms and plenum cover. →92 WINDSHIELD WIPER & WASHER SYSTEM

Fig 2: Identifying Test Box V.A.G 1598/22 Connected To Control Module Wiring Harness

Courtesy of VOLKSWAGEN UNITED STATES, INC.

• Connect test box V.A.G 1598/22 (through my 1999) or test box V.A.G 1598/31 (from my 2000) to control module wiring harness.

Fig 3: 4-Pin Harness Connector & Terminals

Courtesy of VOLKSWAGEN UNITED STATES, INC.

• Check wiring between test box and 4 pin connector for open circuit using wiring diagram:

• Wire resistance: Max. 1.5 Ω

• Check wires for short to one another, to vehicle ground and to battery positive (B+).

• Specification: ∞ Ω

If wiring and resistance measurement values are OK:

• Replace engine control module → Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) J248 , replacing  .