Volkswagen Workshop Service and Repair Manuals

Note:

Check establishes whether Simos control unit (J361) recognises the engine operating modes.

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

Test conditions

• ● Coolant temperature must be at least 80 °C.
• ● Throttle cable adjustment must be OK, checking:

=> Repair group 20; Servicing accelerator mechanism; Adjusting accelerator 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 1 for "Display group number 1" and confirm entry with Q key.

• ‒ Check whether the coolant temperature is above 80 °C in display zone 2.
• ‒ Change to display group 7 as follows:
• ‒ Press C key.
• ‒ Press keys 0, 0 and 7 for "Display group number 7" and confirm entry with Q key.

Engine operating condition (display zone 4):

• ◆ Overrun mode:

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

• 1st position from left must display 1 as long as the engine speed is above 1500 rpm
       Display: 1000

• ◆ Idling:

• 2nd position from left must display 1
       Display: 0100

• ◆ Part throttle:

• ‒ Rev up evenly.

• 3rd position from left must display 1
       Display:: 0010

• ◆ Full throttle:

• ‒ Floor accelerator pedal (onto throttle valve stop).

• 4th position from left must briefly display 1
       Display: 0001

Note:

A test drive may have to be performed to show "Full throttle" in display.

A 2nd person is required when performing a test drive.

• ‒ Press ⇒key.
• ‒ Press keys 0 and 6 for the function "End output" and confirm entry with the Q key.

If the specifications are not attained:

• ‒ Interrogate fault memory, if necessary, repair any faults and then erase fault memory => Page 01-9 , interrogating and erasing fault memory.
• ‒ Check accelerator mechanism for ease of operation.
• ‒ Check throttle valve potentiometer
  => Page 24-34 , Checking throttle valve control part.