FREIGHTLINER, MERCEDES-BENZ · 2022-12-02
Problem: Vehicle fails smog test Cause In the event the Engine Control Module (CDI) detects a fault with the Water Pump Short Circuit to Battery diagnostic, Fault Code P260312 and/or P260315 may set and prevent the readiness monitor from running. Even following a successful repair and/or clearing the Fault Code(s), the readiness monitor remains deactivated and self-healing is not possible. This deactivation may prevent the vehicle from passing state emissions inspection and SMOG Test and is only resolvable by installing new engine control unit software. Remedy 1. Perform XENTRY Quick Test. 2. Check for the presence of Fault Code P260312 and/or P260315 in the CDI control module. 3. If relevant Fault Codes are present, resolve fault using standard dealer procedures. Once fault is resolved,…