Ensure battery is okay. Ensure all fuses are okay, battery voltage is at least 11.5 volts and fuel pump relay is
okay. Ensure all electrical accessories are off and A/C is off.
Test Procedure
1. Connect scan tool. See RETRIEVING DIAGNOSTIC TROUBLE CODES . Turn ignition on, engine
off. Following scan tool manufacturer's instructions, check brake system for DTCs. If no DTCs are
present, go to next step. If DTC(s) are present, repair as necessary. After repairs, erase DTC memory.
Verify repair. Test is complete. Perform ECM relearn procedure. See TEST DRIVE RELEARN
PROCEDURE .
2. Check Brake Servo Pressure sensor (G294) harness connector and wiring. Brake Servo Pressure sensor is
located at front of brake master cylinder. See appropriate WIRING DIAGRAM under ENGINE
PERFORMANCE in SYSTEM WIRING DIAGRAMS. Repair as necessary. After repairs, erase DTC
memory. Verify repair. Test is complete. Perform ECM relearn procedure. See TEST DRIVE
RELEARN PROCEDURE .
DTC P2101/18533: THROTTLE VALVE CONTROL MODULE (J338) - MALFUNCTION
Circuit/Component Description
Throttle Valve Control Module (TVCM - J338) is located on throttle body. Throttle valve drive angle sensors
and are located in TVCM (J338). ECM monitors throttle valve drive angle sensors for throttle valve position.
ECM calculates throttle position based on percentage values sent by throttle valve drive angle sensors. Throttle
valve drive angle sensors run in opposite directions of each other. Throttle Valve Drive Angle sensor No. 1
(G187) displays throttle positions from 3-97 percent. Throttle Valve Drive Angle sensor No. 2 (G188) displays
throttle positions from 97-3 percent. Throttle Valve Drive Angle sensor No. 1 (G187) ranges from 3-93 percent
(0.15-4.65 volts), the larger the throttle opening the higher the percentage (voltage) reading. Throttle Valve
Drive Angle sensor No. 2 (G188) ranges from 97-3 percent (4.90-0.15 volts), the larger the throttle opening the
smaller the percentage (voltage) reading. When the engine is running (under load) the ECM can operate throttle
valve independently of driver input.
Test Requirements
Ensure throttle valve is not damaged or dirty. Ensure all fuses are okay, battery voltage is at least 11.5 volts and
fuel pump relay is okay. Ensure all electrical accessories are off and A/C is off. Ensure engine is mechanically
sound. Ensure no intake or exhaust system leaks exist. Ensure engine coolant temperature is at least 176°F (80°
C).
Test Procedure
NOTE:
If a test ends with ECM replacement. Before replacing ECM be certain that, all
wiring, power and ground supplies are okay. See ENGINE PERFORMANCE in
SYSTEM WIRING DIAGRAMS article in ELECTRICAL and ECM GROUND &
VOLTAGE SUPPLY .
NOTE:
Test ranges for throttle valve drive angle sensors may not fully display on scan
2003 Volkswagen New Beetle GLS
2002-2003 ENGINE PERFORMANCE Self-Diagnostics - 1.8L Turbo
Helpmelearn Repair Manuals
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