What Does bh33 Mean on a Freightliner Truck? – BH 33 code Freightliner

Freightliner Trucks is a semi-truck company based out of the United States. Associated Freightways was created in 1929 as the truck-manufacturing section of Freightliner Corporation. As part of Daimler Truck North America, Freightliner was kept by Daimler AG between 1981 and 2021. (Western Star, Detroit Diesel, and Thomas Built Buses are also on the list.).

As a division of Freightliner, Freightliner Custom Chassis manufactures bare chassis and cutaway chassis for many kinds of vehicles, including vans, medium-duty trucks, and heavy-duty trucks. The Freightliner Argosy was the last cover (COE) semitrailer to be marketed in North America, which was popularized by the business.

Its headquarters are in Portland, Oregon (where it was founded), and automobiles are made in Cleveland and Mount Holly, North Carolina, as well as in Santiago Tianguistenco and Saltillo, Mexico.

Freightways Manufacturing started using the “Freightliner” moniker for their truck construction in the 1930s. To optimize engine power, the trucks experienced a weight drop in addition to their shortened length (required to hike peak grades in the western United States).

One of the most often questions related to Freightliner trucks is:

What does bh33 mean on a Freightliner truck?

BH33 represents a Bulkhead module’s fault code that usually implies a “starter output failed to high side” error or any error related to the starting system. However, you need to use the software program ServiceLink to find the exact problem to detect the error.

bh33 error code

Sometimes, you can go through a menu and retrieve the fault code if you push and hold down the button on your instrument cluster. But the best solution is to use ServiceLink software.

Below you can download Bulkhead Module Fault Code Information Guide.


BH 33 is the identifier for the body controller, often known as your bulkhead module. Fault codes saved in the bulkhead module may be seen or displayed by the mode switch to advance through the screens to the subsequent ones in the sequence. There is a defect code known as BH 33 that is not. This is only a method for identifying the module responsible for producing the error code. It has come to attention that it displays no engine, which often means that the data connection has been unable to communicate successfully. It would help if you ensured that all of your relays and fuses were in working order.

Additionally, check for corrosion and ensure an in-line fuse is in the cable connecting the battery box to the ECM. Check the wiring harness that connects the ECM and the body control for any signs of corrosion or damage to the wires or connecting pins in that harness. In addition to this, you need to inspect all of the power and ground connections that are made to the ECM. Alternately, it might indicate that the power supply to the ECM has been disconnected for whatever reason.

Why does the Freightliner manufactured in 2011 and given the designation BH-33 not start?

A Freightliner M2’s Bulkhead module has a source address of BH-33. You may find this address on the module. Every computer aboard the vehicle communicates with other computers and is connected over the J1939 backbone or data link. Each computer needs its unique “mailing address” to guarantee that messages are delivered to the correct recipients. The number “33” is the address of Bulkhead. The fact that the Bulkhead module has a failure code is not sufficient information to determine the nature of the issue. It is necessary to locate the mistake by using a piece of software known as ServiceLink. The fact that it won’t start as quickly suggests a problem with the wiring, such as “starter output failed to the high side” or anything else influencing the starting process.

In most cases, You may access the error code by depressing and maintaining pressure on a button located on the instrument cluster. If you do not have Service Link, you will be required to take the device to a dealer to have the device removed. The output of the starter is under the management of the Bulkhead module.

Indirect Injection: If you can locate the error code; but, doing so without a laptop that is physically tied to the car would be challenging.

Why does a business class M2, Bh33, have no Trans?

A data link communication error with a “no trans” message indicates that your transmission controller has lost communication. Be careful to check all your fuses and relays in case of a blown a fuse or wiring problem. I’d also double-check your control modules’ power and grounding. It is conceivable that a control module has failed if power and ground are applied to the module, but it does not communicate. Check your wire harness and connection pins for corrosion, damage, and open circuits. Using the mode reset buttons and pressing and holding to advance to the next screen, and pushing briefly to browse through the menu should also provide further fault code information. After that, you’d need to look into each error code individually.

DIAG, which stands for diagnostic, refers to the explanation of the menu screen and is not a problem number, according to my understanding. Once again, pressing and holding the mode reset switch will bring you to the next display, where you may retrieve any error code information.



Robert Aksamit

Robert Aksamit

Robert Aksamit is a mechanical engineer and automotive industry expert. Robert was born in Minnesota and worked in the US automotive industry for 25 years. He is highly regarded for his passion and dedication to continually improving vehicles in response to customer feedback. Robert has a keen eye for sourcing the best vehicle components and materials on the market and is always looking for ways to enhance the user experience. As a writer, Robert covers automotive-related topics. Read more on Robert Aksamit's about page. Contact Robert: robert@promtengine.com

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