2026 Ic Bus Cesb TSBs

Customer requested changes will be approved in accordance with the requirements specified in 40 CFR Part 1037 to ensure continued compliance with greenhouse gas (GHG) regulations.

Customer requested changes will be approved in accordance with the requirements specified in 40 CFR Part 1037 to ensure continued compliance with greenhouse gas (GHG) regulations.

may experience engine stalling, low performance, and/or poor aftertreatment performance. This is caused by condensation accumulating and freezing within the Charge Air Cooler (CAC); affecting air flow into the engine. This article lists currently available winter front covers that can be installed on the front grille and bumper to reduce cold air flow to the engine compartment.

operator may experience engine stalling, low performance, and or poor aftertreatment performance. This is caused by condensation accumulating and freezing within the Charge Air Cooler (CAC); affecting air flow into the engine. This article lists all the currently available winter front covers that can be installed on the front grille and bumper to reduce cold air flow to the engine compartment.

out of adjustment over time and with use. A door that is not adjusted properly may result in an improperly closed door and trigger an open door warning light on the dashboard.

Gen Buses MY2024 through MY2026

See symptoms below for an example of the issue.

(Metric Prop codes start with the number a 4 and Non metric Prop codes start with a 2.)

fault codes after a vehicle sits for 2 or 3 days.

fault codes after a vehicle sits for 2 or 3 days.

prior to 2/19/25

software to support updated Collision Mitigation, Lane Departure Warning (LDW), and Blind Spot Monitoring systems. If replacing the radios on the vehicles described below, the radio either needs to be built after a specific build date or have the software version verified/updated. If outdated radio software is used on these vehicles, the audible tones for these systems may not be heard by the driver. The applicable vehicles were all built with the correct radio. This iKNnow article only applies if replacing the radio for a service event in one of the vehicles listed below.

It allows users to quickly load files either manually or directly from the Diamond Logic Builder Vehicles folder using VIN-based selection. As files are added or removed, the comparison runs automatically with no manual action required. The program presents results in an interactive table that shows feature codes, descriptions, access levels, and whether each feature is present in each selected file. Built-in search, filtering, and sorting make it easy to locate specific features or focus only on differences between files. Column visibility can be customized to show or hide descriptions and access information as needed. Users can remove files individually or clear all files at once, with results updating instantly. The tool also includes reporting and export options that reflect exactly what is visible on screen, allowing results to be printed, copied, saved as text, or exported to CSV for use in Excel or other spreadsheet tools. Overall, the program streamlines the process of comparing vehicle feature configurations, helping users quickly identify differences, validate setups, and document results without manual comparison or external tools.

While the primary focus is on achieving a properly adjusted latching entrance door, it also includes additional helpful tips. Please note that this document is not exhaustive and only addresses some common issues and their resolutions. For more detailed information, refer to Service Manual 0001283373. Also, please check the Service Portal for any open field campaigns for door improvements, such as AFC 26901 for a larger set screw. If this article or the Service Manual does not cover the topic, please create a case file for more specific assistance.

Bus built without the heater option.

This can affect all LT, RH, MV, HV models, 2021MY and up HX, 2024MY and up CE Bus with BCM kernel version 752, 753, and 754. Vehicles built or updated with DLB between 6/1/25 and 11/4/25 are suspected of having these kernels installed on the BCM. The most common complaint is that the steering wheel switches do not function, which, depending on the vehicle model and options, can cause the bus door, pupil warning lights, radio controls, marker interrupt, and cruise control to stop working. Other complaints can include short circuit faults from multiple sensor circuits attached to the BCM setting at the same time, the vehicle will not go into gear, the headlights are stuck on, the brake lights are stuck on, or the parking brake alarm is sounding (horn chirping) with the parking brake set. As of 11/4/25, these symptoms can be resolved by updating the BCM to kernel 755 or later with DLB.

windshields using an ultrasonic sound detector.