Wastegate Bypass Regulator Valve -N75-, Checking

Wastegate Bypass Regulator Valve -N75-, Checking







Recommended special tools and equipment
- V.A.G1526A hand multimeter
- V.A.G1594A connector test kit
- V.A.G1598/31 test box

Test requirements:
- Fuse for wastegate bypass regulator valve OK
- Fuel Pump (FP) Relay OK; checking.
- Ignition switched off.

NOTE: Voltage for Wastegate Bypass Regulator Valve -N75- is supplied via the fuel pump relay.

Procedure
- Disconnect electrical harness connector at Wastegate Bypass Regulator Valve -N75-.

Checking internal resistance







- Connect multimeter at valve for resistance measurement.

Specified value: 25 to 35 Ohms

If specified value is not obtained.
- Replace Wastegate Bypass Regulator Valve -N75-.

If specified value is obtained:

Checking voltage supply







- Connect multimeter between terminal 1 and 2 for voltage measurement.
- Operate starter briefly.

Specified value: approx. battery voltage

If there is no voltage:
- Connect multimeter for voltage measurement as follows:

Harness connector Terminal Measure to
1 Engine Ground (GND)

- Operate starter briefly.

Specified value: approx. battery voltage

- Switch ignition off.

If there is no voltage again:
- Check wire connection from harness connector terminal 1 to Fuel Pump (FP) Relay -J17- via fuse for open circuit according to wiring diagram.

Specified value: Wire resistance max 1.5 Ohms

- If necessary, repair wire connection.

If voltage supply is OK:

Check Ground (GND) activation







- Connect multimeter for voltage measurement as follows.

Harness connector Terminal Measure to
2 B+

- Operate starter briefly.

Specified value: approx. battery voltage

- Switch ignition off.

If specified value is not obtained:
- Connect test box to wiring harness of Engine Control Module (ECM). ECM is not connected.







- Check the following wire connection for open circuit according to wiring diagram.

Harness connector Terminal Test box Socket
2 104

Specified value: Wire resistance max 1.5 Ohms

- Also check the wire for short circuit to B+ and Ground (GND).

Specified value: Infinite Ohms (no continuity)

- If necessary, repair wire connection.

If no malfunctions are found in wires:
- Replace Engine Control Module (ECM).

Final procedures
After repair work, the following work steps must be performed in the mentioned sequence:
1. Check DTC memory.
2. If necessary, erase DTC memory.
3. Generate readiness code. With Generic Scan Tool

- End diagnosis and switch ignition off.