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Reading measured value block > < Erasing fault memory

Passat (B3)

Diesel injection and glow plug system
Self diagnosis
Final control diagnosis

Special tools, testers and auxiliary items

  • ◆ Fault reader V.A.G 1551 with cable V.A.G 1551/3
  • ◆ Diode test lamp V.A.G 1527

The final control diagnosis activates the following components in the stated sequence:

1. Exhaust gas recirculation valve (N18)

2. Idling speed boost valve (N177)
     (only with air conditioner)

3. Glow period warning lamp (K29)

4. Glow plug relay (J52)

5. Engine/air conditioner compressor electrical connection
     (only with air conditioner)

6. Commencement of injection valve (N108)

Notes:

  • ◆ During the final control diagnosis the individual final controls are activated by pressing the ⇒key. They will remain activated until the ⇒key is pressed again.
  • ◆ The ignition must be switched off before repeating the final control diagnosis.
  • ◆ The final control diagnosis can be carried out with the engine stationary or running. As the clicking of the valves when being activated can be heard better with the engine stationary. it should be carried out with the engine stationary.

Work sequence

  • ‒ Connect fault reader V.A.G 1551 and select Diesel injection pump electronics control unit (address word 41); selection is carried out with ignition switched on.
 
→ Indicated on display:
Rapid data transfer     HELP
Select function XX
  • ‒ Operate fault reader taking into account the information on the display:
  • ‒ Input 03 for "Final control diagnosis" function.
 
→ Indicated on display:
Rapid data transfer     Q
03 Final control diagnosis

Note:

If something different is indicated on the display =>Fault reader operating instructions.

  • ‒ Confirm entry with Q key.
 
→ Indicated on display:
Final control diagnosis     ⇒
Exhaust gas recirculation valve -N18
  • The valve will be activated and must click once.
  • ‒ Press ⇒ button.
 
→ Indicated on display:
Final control diagnosis     ⇒
Exhaust gas recirculation valve -N18
  • Valve activation will be switched off and the valve must again click once.

Valve does not click:

  • ‒ Checking exhaust gas recirculation:

=> 4-Cyl. Diesel engine, Mechanics; Repair group 26; Checking exhaust gas recirculation

  • ‒ Press ⇒ button.
 
→ Indicated on display:
Final control diagnosis     ⇒
Idling speed boost valve -N177
  • The valve will be activated and must click once.
  • ‒ Press ⇒ button.
 
→ Indicated on display:
Final control diagnosis     ⇒
Idling speed boost valve -N177
  • Valve activation will be switched off and the valve must again click once.

Valve does not click:

  • ‒ Check wiring and connections according to current flow diagram.
  • ‒ Check idling speed boost valve => Page 23-39
  • ‒ Press ⇒ button.
 
→ Indicated on display:
Final control diagnosis     ⇒
Glow period warning lamp -K29
  • The warning lamp must light up.

Warning lamp does not light up:

  • ‒ Check glow period warning lamp:

=> Current flow diagrams, Electrical fault finding and Fitting locations binder

  • ‒ Press ⇒key.
 
→ Indicated on display:
Final control diagnosis     ⇒
Glow period warning lamp -K29
  • The warning lamp must go out.
  • ‒ Press ⇒ button.
 
→ Indicated on display:
Final control diagnosis     ⇒
Glow plug relay -J52
  • The glow period is switched on and the relay must click once
  • ‒ As a check the diode test lamp V.A.G 1527can be connected to the glow plug feed wire.
         LED must light up.
  • ‒ Press ⇒key.
 
→ Indicated on display:
Final control diagnosis     ⇒
Glow plug relay -J52
  • The glow period is switched off and the relay must again click once or LED must go out.

If the relay does not click:

  • ‒ Check glow plug relay:

=> Current flow diagrams, Electrical fault finding and Fitting locations binder

  • ‒ Press ⇒key.
 
→ Indicated on display:
Final control diagnosis     ⇒
Engine/ACC electrical connection
  • The air conditioner compressor must stop within 5 secs. (visual check), and then start running again.

If the conditioner compressor is not switched off:

  • ‒ Check conditioner compressor shut-off:

=> Current flow diagrams, Electrical fault finding and Fitting locations binder

  • ‒ Press ⇒key.
 
→ Indicated on display:
Final control diagnosis     ⇒
Engine/ACC electrical connection
  • ‒ Press ⇒key.
 
→ Indicated on display:
Final control diagnosis     ⇒
Commencement of injection valve -N108
  • The valve will be activated and must click once.
  • ‒ Press ⇒key.
 
→ Indicated on display:
Final control diagnosis     ⇒
End output
  • Valve activation is switched off and the valve must again click once.

Valve does not click:

  • ‒ Check wiring and connections according to current flow diagram.
  • ‒ Check commencement of injection valve => Page 23-38
  • ‒ Press ⇒key.
 
→ Indicated on display:
Function is not known     ⇒
or cannot be performed at the moment
  • ‒ Press ⇒ button.
 
→ Indicated on display:
Rapid data transfer     HELP
Select function XX
  • ‒ Input 06 for "End output" function and confirm with Q.
  • ‒ Switch off ignition.

Reading measured value block > < Erasing fault memory