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Home >> Volkswagen >> 2003 >> Golf GLS, 1.9 P, Standard >> Repair and Diagnosis >> Engine Performance >> System >> 1.9L - TDI And TDI Pd Generic Scan Tool, Engine Code(S): ALH, BEW (A4 Platform) >> 28 Ignition/Glow plug system >> Glow plug system, checking >> Glow plug system, checking >> Only vehicles with engine code BEW and vehicles with engine code ALH, model year >2001 >> Test sequence
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Test sequence

Vehicles with 80-pin control module 

Fig 1: ECT Sensor
GW00001078Courtesy of VOLKSWAGEN UNITED STATES, INC.

Vehicles with 121-pin control module 

Fig 2: ECT Sensor Terminals 1 & 3
GW00001105Courtesy of VOLKSWAGEN UNITED STATES, INC.

Vehicles with 154-pin control module 

Fig 3: Engine Coolant Temperature Sensor Connector
GW00001117Courtesy of VOLKSWAGEN UNITED STATES, INC.

Continue for all vehicles 

NOTE: By disconnecting the connector from the sensor, a "cold" engine state is simulated and a corresponding glow plug procedure is performed when ignition is switched on.

Vehicles with engine code ALH 

Battery voltage for approx. 20 s.

Vehicles with engine code BEW 

Battery voltage for approx. 20 s.

Continue for all vehicles 

Refer to Electrical Wiring Diagrams, Troubleshooting & Component Locations