Throttle Full Close Switch: Testing and Inspection

The Closed Throttle Position (CTP) switch is electrically closed (continuity) when the throttle valve is closed (at idle), and electrically open (no continuity) as soon as the throttle is opened.

CHECKING CTP SWITCH

Underhood Component Location Rear:

- Remove noise damper from top rear of engine, position # 3 in image.

Throttle Body:

- Disconnect harness connector from the CTP Switch / Throttle Position Sensor (TPS), located at the bottom the throttle valve housing.

Throttle Position Switch/Sensor Terminals:

- Using suitable multimeter set to resistance range, and throttle valve closed (idle position) check for continuity between CTP Switch terminals 4 and 6.
^ Must be approximately 0 ohms (continuity)
^ IF NOT, CTP Switch adjustment is needed

- Open throttle valve approximately 10% of travel, check for continuity between CTP Switch terminals 4 and 6.
^ Must be infinite ohms (open)
^ IF NOT or only when throttle is opened more than 10% of travel, CTP Switch adjustment is needed

NOTE:
When installing the noise insulation, make sure noise insulation fits tightly on throttle body to prevent air leaks.
Check the output voltage of the Mass Air Flow (MAF) sensor to be sure, Refer to On Board Diagnotic, "Basic Setting" function 04, display group 002, display field 2

CHECKING WIRING TO ENGINE CONTROL MODULE
- Connect VAG 1598 test box with adapter harness VAG 1598/11 to the Engine Control Module (ECM) wiring harness.
^ Adapter harness for ECM is not connected.

6-Pin Connector:

- Check wiring for continuity and/or short circuit to positive (B+) between Throttle Position Sensor (TPS) connector Ground (GND) terminal 4 and GND connection on right engine compartment wiring harness.
^ Specified value: maximum 1 ohms
- Check wiring for open circuit or short circuit to ground between TPS connector terminal 6 and test box socket 49.
^ Specified reading: maximum 1 ohms

If specified values are not obtained:
- Determine open and/or short circuit in wiring harness between 6-pin TPS connector in engine compartment and ECM connector A according to wiring diagram, and repair.

6-pin connector ECM connector A
6 9
4 Ground (GND)

NOTE:
Use only gold-plated terminals to replace terminals on the TPS connector.