SEAT Workshop Service and Repair Manuals

Note:

Checks whether engine control unit recognises the engine operating modes idling, overrun, part throttle and enrichment.

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required

• ◆ Fault reader V.A.G 1551 or vehicle system tester V.A.G 1552 with cable V.A.G 1551/3

Check conditions

• ● Coolant temperature at least 85 °C.
• ● Throttle cable adjustment must be OK, checking:

=> Repair group 20; Accelerator mechanism; adjusting throttle cable

Test sequence

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

• ‒ Press keys 0 and 8 for the function "Read measured value block" and confirm entry with Q key.

• ‒ Press keys 0, 0 and 3 for "Display group number 3" and confirm entry with Q key.

• ‒ Check whether the coolant temperature is above 85 °C in display zone 3.
• ‒ Change to display group 4 as follows:
      V.A.G 1551: Press key 3
      V.A.G 1552: Press key ↑

Display for operating modes in display zone 4:

• ◆ Idling:

• As long as the engine is running at idling speed idling must be displayed
      Display: Idling

• ◆ Overrun mode:

• ‒ Increase engine speed to above 3000 rpm.
• ‒ Close throttle abruptly.

• As long as the engine speed is above 1400 rpm overrun must be displayed
      Display: Overrun

Note:

Below 1400 rpm idling speed will be recognised.

• ◆ Part throttle:

• ‒ Rev up evenly.

• As long as the engine is being revved up evenly, part throttle must be displayed
      Display: Part throttle

• ◆ Enrichment:

• ‒ Quickly increase engine speed.

• Enrichment must be displayed briefly
      Display: Enrichment

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

If the specifications are not attained:

• ‒ Interrogate fault memory, if necessary, repair any faults and then erase fault memory => Page 01-10, interrogating and erasing fault memory.
• ‒ Check accelerator mechanism for ease of operation.
• ‒ Check throttle valve potentiometer
  => Page 24-30, Checking throttle valve control part.