audi Workshop Repair Guides

Audi Workshop Service and Repair Manuals

ABOUT US
Checking intake manifold pressure sender -G71 > < Boost pressure control connection diagram - engine codes ALH, AHF, ASV

A3 Mk1

4-cyl. Diesel Direct Injection Engine (TDI), Mech. Components
Checking charge air system with turbocharger
Checking solenoid valve for boost pressure limitation -N75
 
A10-0121

Checking internal resistance

Engine code AGR:

  • ‒ Switch ignition off.
  • ‒ → Disconnect electrical connector at boost pressure limitation solenoid valve -N75 -Item 2-.
 
N23-0015
  • ‒ → 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.
 
A21-0256

Engine codes AHF, ALH, ASV:

  • ‒ Switch ignition off.
  • ‒ → Disconnect electrical connector at boost pressure limitation solenoid valve -N75 -Item 2-.
 
A23-0085
  • ‒ → 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.
 
A23-0037

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:
 
N24-0709

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

Important
To prevent damage to the electronic components, select appropriate measuring range before connecting the measuring cables and observe the test requirements.
 
A23-0037
  • ‒ → 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.
 
A24-0198

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

Important
To prevent damage to the electronic components, select appropriate measuring range before connecting the measuring cables and observe the test requirements.
 
A23-0037
  • ‒ → 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.

Checking intake manifold pressure sender -G71 > < Boost pressure control connection diagram - engine codes ALH, AHF, ASV