Checking Idle and/or ECM Partial Load Recognition Function

If not already installed, connect the (VAG 1551) Scan Tool. See CONNECTING SCAN TOOL (VAG 1551) .

1. Using VAG 1551 Scan Tool. Select "READ MEASURING VALUE BLOCK" function 08. Input display group number 04. See READING/MEASURING VALUE BLOCK (FUNCTION 08) under OUTPUT DIAGNOSTIC TEST MODES (DTM) in SELF-DIAGNOSTICS article.
2. Observe display values in channel 4, performing the following. Apply Accelerator Pedal (AP) slightly (a few millimeters). Two digits of the 5-digit display number, must change:
   • 3rd digit: changes from 0 to 1.
   • 4th digit: changes from 1 to 0.
3. If value changes (but only after additional pedal travel). Adjust Closed Throttle Position (CTP) switch. See THROTTLE POSITION SENSOR . If display does NOT change. Check CTP switch and wiring connections. See CHECKING CLOSED THROTTLE POSITION SWITCH .
4. If digits have already changed prior to accelerator pedal application:
   • 3rd digit already changed to 1.
   • 4th digit already changed to 0.
5. Adjust CTP switch. See THROTTLE POSITION SENSOR . If after adjusting (previous step), fault is still present. Check CTP switch and wiring connection. See CHECKING CLOSED THROTTLE POSITION SWITCH .

Fig 1: Identifying Throttle Position (TP) Sensor Terminals

Courtesy of AUDI OF AMERICA, INC.

Fig 2: Identifying MAF & TP Sensor 6 Pin Wiring Harness Connector

Courtesy of AUDI OF AMERICA, INC.