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Golf VII · 1.2 TSICurrent vehicle

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Volkswagen Golf VII1.2 TSI · 77 kW

Engine code CJZA
Production 2012–2015
6-speed manual
Drivetrain FWD
Configuration: VIN decoded

Engine code CJZAProduction 2012–20156-speed manualDrivetrain FWDConfiguration: VIN decodedConfiguration: VINVIN decoded

Overview
Parts
Procedures
Torque
Fluids
Maintenance
Diagnostics
Wiring
Specs
Bulletins
Locations
Connectors
Sources

Overview
Parts
Procedures
Torque
Fluids
Maintenance
Diagnostics
Wiring
Specs
Bulletins
Locations
Connectors
Sources

MoreMore

OverviewOverviewPartsPartsProceduresProceduresTorqueTorqueFluidsFluidsMaintenanceMaintenanceDiagnosticsDiagnosticsWiringWiringSpecsSpecsBulletinsBulletinsLocationsLocationsConnectorsConnectorsSourcesSources

ExampleExample data, not a real vehicle

Overview
Parts
Procedures
Torque
Fluids
Maintenance
Diagnostics
Wiring
Specs
Bulletins
Locations
Connectors
Sources

Diagnostics
ABS/ESP

U0121, Lost communication with anti-lock brake system (ABS) control module

Lost communication with anti-lock brake system (ABS) control module

Severity: HighExample

Module: ABS/ESP
Type: Generic (SAE)
Applicability: All configurations
Source: Codes · U0121

Conditions for setting Placeholder: ignition on or vehicle moving, fault present for the debounce time.

Diagnostic steps

Preliminary checks. There is no guided test for this code in the example data.

Example

Preliminary checks

Read and note all stored codes and freeze-frame data.
Check the relevant connectors and harness visually.
Clear the codes and repeat the conditions for setting.
Work through the possible causes in order.

The related wiring and procedures are listed belowalongside.

Possible causes

In the order the source lists them, with no likelihoods.

Example

ABS control module supply or ground fault
Data bus wiring fault
Control module faulty

Wiring

ABS control unit supplyBrakes / ABS · sheet 1 · MX-WD-5G-04

Procedures

No procedure linked to this code in the example data.

Service bulletins

No bulletin mentions this code.

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