Checking solenoid valve for boost pressure limitation -N75 — AUDI

AHF ALH ASV
Checking internal resistance

Engine code AGR:

Switch ignition off.
Disconnect electrical connector at boost pressure limitation solenoid valve -N75 -Item 2-.

Connect multimeter to injector to measure resistance.
Specified value: 25...45 ω

If specified value is not attained:

Replace solenoid valve for boost pressure control -N75.

Engine codes AHF, ALH, ASV:

Switch ignition off.
Disconnect electrical connector at boost pressure limitation solenoid valve -N75 -Item 2-.

Connect multimeter to injector to measure resistance.
Specified value: 14 ... 20 ω

If specified value is not attained:

Replace solenoid valve for boost pressure control -N75.

All models:

If specified value is attained:

Checking power supply

Connect multimeter between contact 1 and earth to measure voltage.
Switch the ignition on.
Specified value: approx. battery voltage

If specified value is not attained:

Check wiring for open circuit and service if necessary.

If specified value is attained:

Checking actuation - Vehicles up to 07.99

Connect the test box V.A.G 1598/22 to wiring harness connectors; the engine control unit must not be connected.

=> Diesel Direct Injection and Glow Plug System (4-cyl TDI) > 07.99; Repair group 23; Wiring and component check using test box V.A.G 1598/22
Diesel Direct Injection and Glow Plug System (4-cyl TDI) > 07.99
Wiring and component check using test box V.A.G 1598/22

Important
To prevent damage to the electronic components, select appropriate measuring range before connecting the measuring cables and observe the test requirements.
Check for open circuit and short to positive or earth in the following wiring connection:

Connector / Contact · Test box V.A.G 1598/22 / Socket
2 · 15

Rectify any open/short circuit as necessary.

Checking actuation - Vehicles as of 08.99

Connect the V.A.G 1598/31 test box to wiring harness connectors; the engine control unit should not be connected. Attach the earth clip of test box to earth -arrow-.

=> TDI Injection and Glow Plug System (4-cyl.) 08.99 >; Repair group 23; Wiring and component check using test box V.A.G 1598/31
TDI Injection and Glow Plug System (4-cyl.) 08.99 >
Wiring and component check using test box V.A.G 1598/31

Important
To prevent damage to the electronic components, select appropriate measuring range before connecting the measuring cables and observe the test requirements.
Check for open circuit and short to positive or earth in the following wiring connection:

Connector / Contact · Test box V.A.G 1598/31 / Socket
2 · 62

Rectify any open/short circuit as necessary.