LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mercedes Benz >> 2000 >> SL600 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics With Codes >> Diagnostic Tests >> DTC P0135: O2 Sensor Heater Of Right O2 Sensor Upstream TWC (G3/4) >> Testing Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Testing Procedure

NOTE: For ME-SFI control module location and identification, see ME-SFI CONTROL MODULE CONNECTOR IDENTIFICATION  .
  1. Actuation -  Connect DVOM between right cylinder bank ME-SFI control module connector 1 terminals No. 13 and 25 (socket box terminals No. 13 and 25). Start engine and idle. Allow engine to idle for at least 2 minutes after engine coolant temperature reaches more than 176°F (80°C). Voltage should be 11-14 volts. If voltage is within specification, go to next step. If voltage is not within specification, possible causes are wiring harness failure, O2 sensor (G3/4) failure or defective right cylinder bank ME-SFI control module (N3/12).
  2. Current Consumption -  Turn ignition off. Connect ammeter between right cylinder bank ME-SFI control module connector 1 terminals No. 26 and 13 (socket box terminals No. 26 and 13). Turn ignition on. Ammeter should indicate 0.6-3.4 amps. If amperage is within specification, test is complete. If amperage is not within specification, possible causes are wiring harness failure, O2 sensor (G3/4) failure or defective right cylinder bank ME-SFI control module (N3/12). Repair as necessary.