SEAT Workshop Service and Repair Manuals

Special tools, testers, measuring instruments and auxiliary items required

• ◆ Fault reader V.A.G 1551 with cable V.A.G 1551/3

Test requirements for vehicles with air conditioning system

• ● Vehicle at room temperature (warmer than + 15 °C)
• ● Air conditioning system switched on
• ● Select lowest temperature and highest blower speed

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

1. Commencement of injection valve (N108)

2. Exhaust gas recirculation valve (N18)

3. Conditioner compressor interruption

4. Fuel cut-off valve (N109)

5. Solenoid valve for boost pressure control (N75)

6. Glow plug relay (J52)

7. Glow period warning lamp (K29)

8. Fan relay (J323)

Notes:

• ◆ Activation of individual control elements is limited to 30 seconds but can be stopped at any time by pressing the ⇒button.
• ◆ The ignition must be switched off before repeating the final control diagnosis.

Work sequence

• ‒ Connect fault reader V.A.G 1551 (V.A.G 1552) and select engine electronics control unit with the "Address word" 01. When doing this the engine must be running at idling speed.
  (Connecting fault reader and selecting engine electronics control unit .)

• ‒ Operate fault reader taking into account the information on the display:
• ‒ Press keys 0 and 3 for the function "Final control diagnosis".

• ‒ Confirm input with Q key.

• Activating the valve, influences the noise of combustion considerably (pre-ignition).

If no changes in the combustion noises are heard:

• ‒ Check injection adjuster control range
  => Page 23-70
• ‒ Press the ⇒key.

• The valve must click.

Notes:

• ◆ Because of engine noises the clicking of the valve cannot be heard and therefore must be felt to detect its operation.
• ◆ The piston movement of the mechanical exhaust gas recirculation valve is visible in the side slot.

Valve does not click:

• ‒ Check exhaust gas recirculation and air mass meter function => Page 23-89
• ‒ Press the ⇒key.

• Air conditioner compressor switch-off is checked.
• The test step is also called on vehicles without air conditioner system.
• The conditioner compressor must stop within 5 seconds (visual check) then start approx. every 5 seconds and then stop.

If the conditioner compressor is not switched off:

• ‒ Check conditioner compressor cut-off:

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

• ‒ Press the ⇒key.

• The engine must stop.

If the engine does not stop:

• ‒ Switch off ignition.
• ‒ Unscrew fuel cut-off valve and remove any metal particles or dirt.
• ‒ Repeat final control diagnosis and if the engine will not stop replace fuel cut-off valve.
• ‒ Continue final control diagnosis with engine stopped and ignition switched on.
• ‒ Press the ⇒key.

• The solenoid valve must click.

Note:

The clicking of the valve is difficult to hear and is therefore best checked by touch.

If the solenoid valve does not click:

• ‒ Check charge pressure limiting solenoid valve (N75) => Page 23-79.
• ‒ Press the ⇒key.

• The relay must click.
• Switching on and off the relay can also be observed as the interior light becomes brighter and darker as a result of the glow plug high power consumption.

If the relay does not click:

• ‒ Check glow plug relay:

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

• ‒ Press the ⇒key.

• The control lamp must flash.

Control lamp does not flash:

• ‒ Check glow period warning lamp:

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

• ‒ Press the ⇒key.

• The fan must run every 5 seconds and then stop again.

If the fan does not run:

• ‒ Check the fan relay:

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

• ‒ Press the ⇒key.

• ‒ Press keys 0 and 6 for the "End data transfer" function and confirm input with the Q key.
• ‒ Switch off ignition.