2010 Mercedes Benz Truck GL 350 BLUETEC (164.825) V6-3.0L DSL Turbo (642.820)
Vehicle: All Technical Service Bulletins
Engine Controls - Short Circuit O2 Sensor DTC's Stored
Short circuit faults concerning oxygen sensor stored in CDI control unit
Topic number LI49.20-P-053609
Version 1
Design group 49.20 Exhaust aftertreatment unit
Date 04-05-2012
Validity Model 164 with engine 642 and SA code U42 (BlueTEC (SCR) diesel exhaust treatment)
Reason for change
Complaint:
Engine diagnosis warning lamp CEL) lights up
The following faults may be stored in the CDI control unit:
Fault code 14E300
The output for the heater of oxygen sensor 1 (cylinder bank 1) has an electrical fault or an open circuit
Fault code 14E700
Oxygen sensor 1 (cylinder bank 1) has a short circuit to positive
Fault code 14E800
Oxygen sensor 1 (cylinder bank 1) has a short circuit to ground
Cause:
There may be transition resistances in the electrical lines or connectors between N319 (CDI control unit) and the component G312 (02 sensor
upstream of catalytic converter).
Remedy:
1. Check connector between N3/9 (CDI control unit) and the component G3/2 (02 sensor upstream of catalytic converter) for correct connection
/ corrosion. Clean contacts and / or re-connect.
If there are connector issues, continue with step 2.
2. Process the test steps in Star Diagnosis for these fault codes. If a fault is found, follow the continuing diagnosis instructions.
If no faults are found, please submit the case to the DTS and clear the CEL.
Symptoms
Control Unit / Fault Code
Work Units
