Passat Sedan L4-2.0L Turbo (BPY) (2007)
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Vehicle Speed Sensor: Testing and Inspection
Speed Signal, Checking
The following procedure requires a test drive. Observe all safety precautions. Refer to => [ Observe the following if test
and measuring instruments are required during a test drive: ] See: Fuel Delivery and Air Induction/Service Precautions/Safety Precautions/Multiport Fuel
Injection (MFI).
Special tools, testers and auxiliary items required
‹› Multimeter.
‹› Wiring diagram.
Test requirements
‹› The Speedometer (G21) OK.
‹› The Motronic Engine Control Module (ECM) (J623) fuses OK.
‹› Battery voltage at least 12.5 volts.
‹› All electrical consumers such as, lights and rear window defroster, switched off.
‹› A/C switched off.
‹› Ground (GND) connections between engine/transmission/chassis OK.
‹› Ignition switched off.
Function test
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Connect the scan tool.
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Perform a road test with a vehicle speed greater than 5 Km/h.
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Using the scan tool, Check the vehicle speed:
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Compare the vehicle speed on the scan tool to the Speedometer (G21).
Specified value: a difference of no greater than 10%.
If the specified value was not obtained or no speed was displayed:
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Check the wiring from the Motronic Engine Control Module (ECM) (J623) to the Instrument Cluster Control Module (J285) for an open circuit,
Short to Battery (+), or to Ground (GND).
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Check the wiring connection for damage, corrosion, loose or broken terminals.
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If necessary, repair the faulty wiring connection.
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Assembly is performed in the reverse of the removal.
Final Procedures
After the repair work, the following work steps must be performed in the following sequence:
1. Check the DTC memory. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] See: Testing and Inspection/Scan Tool Testing and
Procedures/Diagnostic Modes 01 - 09/Diagnostic Mode 03 - Read DTC Memory.
2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] See: Testing and Inspection/Scan Tool Testing
