Oxygen sensor heater, checking: Notes

Recommended special tools and equipment 

• V.A.G 1526 multimeter or V.A.G 1715 multimeter
• V.A.G 1594 connector test kit
• Wiring diagram

Requirements 

• The respective fuses of Diesel-Direct fuel injection system must be OK:

Refer to Electrical Wiring Diagrams, Troubleshooting & Component Locations

• Battery voltage must be at least 11.5 volts.
• All electrical consumers such as, lights and rear window defroster must be switched off.
• For vehicles with automatic transmission, selector lever must be in -P-.
• Parking brake must be engaged.

• If vehicle is equipped with an A/C system, it must be switched off.
• Ground (GND) connections between engine and chassis must be OK.
• Coolant temperature must be at least 80 ° C. Refer to Diagnostic mode 1: Check measured values 
• Ignition is switched off.

Test sequence 

• Disconnect 6-pin harness connector -1- to Heated Oxygen Sensor (HO2S) -G39-.

• Check resistance for sensor heater at connector to oxygen sensor terminal 3 + 4.

Specified value: Max. 10 Ω (at room temperature)

If specified value is not obtained:

• Replace Heated Oxygen Sensor (HO2S) -G39-. Refer to Front exhaust pipe and catalytic converter with attachments  , item 3 .
• Erase DTC memory of Engine Control Module (ECM). Refer to Diagnostic mode 4: Reset/erase diagnostic data 
• Generate readiness code. Refer to Readiness code, generating 

If specified value is obtained:

• Check voltage supply and wiring to Engine Control Module (ECM). Refer to Oxygen sensor heater, checking  .