P0B74 OBD Error Code: Problem & Solutions

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Error code P0B74? Stressed? Well, we have got it all! Here’s all that you need to know about the error code P0B74. This generic OBD-II code increased fuel consumption is also referred to as a hybrid battery voltage sense "L" circuit low. A pack of mini-batteries all connected together all present in the high voltage battery pack. Whenever, there is a defect detected by the high voltage control module in one or more than one battery packs that are there in the high voltage battery assembly, the code P0B74 is stored by the high voltage control module.

It should be noted that the hybrid/electric vehicle battery pack has a total of 96 cells in it. Also, sets of three cells are fused together in parallel. Overall 96 cell groups are present in the hybrid/EV battery pack assembly. All of these cell groups are connected using an electrical connection in-series. A single cell group is ranked at 3.7 V for a formal system voltage of 355 V direct current. These battery cells present are further also sectioned into three equal parts. The battery section one includes the first 90 cells/30 cell groups. This section is situated close to the cowl and consists of batteries from 67 to 96. In Front of the battery section two is the section one. Composed of 72 cells/24 cell groups it contains batteries numbering from 43 to 66. The transverse battery section is labelled as the battery section three. It consists of the rest of the 126 cells/42 cell groups and batteries ranging from 1 to 42. All the three battery sections are separately serviceable parts.

Also, the task of regulating the voltage of the 96 battery cell groups through the four hybrid/EV battery interface control modules is performed by the the battery energy control module. The voltage sense circuits can be observed linked to each individual cell group. At a connector situated on the top surface area of the battery section, one can see these voltage sense circuits terminating. An auxiliary battery wiring harness that can be serviced individually is used to link this connector to a hybrid/EV battery interface control module. This is also located on the top surface of the battery section. The hybrid/EV battery interface control module performs the essential function of encoding the voltage reading and further imparting it to the battery energy control module by the way of the battery control harness. In all, there is one hybrid/EV battery interface control module placed on the battery sections one and two while there are two hybrid/EV battery interface control modules connected to the battery section three. The parts namely the hybrid/EV battery interface control module, battery energy control module wiring harness, auxiliary battery wiring harness, and battery energy control module are all valid for servicing.

The battery energy control module constantly updates whenever there is a fault present. Via serial data, the diagnostics and system status are forwarded from the battery energy control module to hybrid/EV powertrain control module 2. The hybrid/EV powertrain control module 2 is considered to be the chief controller for all the diagnostic trouble code information.

 What causes this problem with the Hybrid Battery Voltage Sense "L" Circuit Low?

• A fault in the hybrid/electric vehicle battery pack
• A malfunctioning hybrid/electric vehicle battery interface control module

1. Hybrid battery - A significant fall in the miles per gallon is the likely to be observed when there is fault in the hybrid battery. The internal combustion will also be experienced to be more than usual (the span of the ICE is said to be reduced). So in order to remove the error the code P0B74, we advise you to change or repair your hybrid battery right away. Tune into Parts Avatar for premium quality products.
2. Hybrid battery pack - The engine making a cranking noise, difficulty in starting the vehicle, swollen car battery system and a drained battery are the most common things triggered by the faulty hybrid battery pack. If you are experiencing all this then we recommend you to tune into Parts Avatar to find the right products and the apt solutions for your problem.
3. Hybrid battery voltage sensor - Engine surging, low battery voltage and illuminated battery lights. If you are observing all this it could likely be due to a malfunction in the hybrid battery voltage sensor. Tune into Parts Avatar for premium quality products.
4. Battery cable - Bad battery cables apart from resistance problems also hold a potential for causing a sudden fire in the system. Not only this a bad battery cable also deteriorates the abilities of a new battery installed. Tune into Parts Avatar for new battery cables as soon as possible to avoid a problem on your new battery.
5. Battery assembly - These perform the function of connecting the various electrical components and also joins the battery cables to the battery assembly. Also, this plays a major role in the functioning of the battery. It is advised to change your battery assemblies just in time to avoid further expensive repairs and replacements. Tune into Parts Avatar now!
6. Battery control module - As the name rightly suggests this serves various purpose right from regulating the temperatures to maintaining a balance in the system voltage. A lot is at stake if the battery control module is diagnosed to be damaged. Restore or mend it now.
7. Powertrain control module - A number of erratic symptoms are likely to be experienced as soon as the PCM gets damaged. The powertrain control module enables the system and transmission to work in tandem. So a faulty PCM can affect not only a few parts but the functioning of the entire system. Tune into Parts Avatar for top notch sets of PCM.
8. Exhaust system parts - The exhaust system parts play the essential role of withstanding all the heat and high stress of the engine’s exhaust. So they are prone to easy corrosion. A corrosion in any of these parts can lead to a fire in all the exhaust parts in the system. We recommend you to change or replace them just in time before it's too late.
9. Battery smart unit - See the error code P0B74 flashing? Well, a malfunctioning battery unit not only holds the potential for ruining the battery but also the entire system. A sluggish engine crank, fall in the battery power and the turning on of the check engine lights is likely to accompany a fault in the battery smart unit.

Willing to know some common symptoms of OBD Code P0B74? Your wish is our demand. Have a look at them below:

Common Symptoms

• Rise in the fuel consumption
• Engine light flashing on (or service engine soon warning light)

Want to correct the Trouble Code P0B74? Read these points mentioned below:

• Repair or replace a distorted hybrid/electric vehicle battery pack
• Take measure to fix your damaged hybrid/electric vehicle battery interface control module
• Immediate replacements or repairs should be performed if your exhaust system parts are found to be defective
• A malfunctioning electronic control unit should be changed or repaired too
• A mendments should be performed to fix a distorted powertrain control module

The engine system, in conjunction with the engine control module (ECM)/powertrain control module (PCM), activates the P0B74 code solenoid valve to control oil pressure to the engine mechanism that is installed in the valve system to switch valve timing between Low and High.If the engine solenoid valve has an open or short circuit, a DTC is stored.

There is no need to get strained if your OBD code is still flashing up as we are here at your service. Have a look at our superior variety of hybrid battery, hybrid battery pack, hybrid battery voltage sensor, battery cable, battery assembly, battery control module, powertrain control module, battery connection, exhaust leak, battery smart unit, mass air flow sensor, automatic transmission module, control module, body control module, abs module, ecm module, pcm module, electronic control module, brake control module and many more. Now all your problems would vanish within no time.

Here are some steps which you should follow in order to diagnose this fault code P0B74:

To begin the diagnosis, the first step of the mechanic should be using a scanner (or code reader) and a digital volt/ohmmeter as these will be helpful in successfully diagnosing this code-storing condition. Next, it is essential to your diagnose with a visual inspection of system wiring, connectors, and components. It is recommended to restore or mend any open, shorted, damaged, or corroded items as required and retest the system to make sure that repairs were successful. If the system wiring, connectors, and components appear to be in normal working order, connect the scanner to the diagnostic connector and record all stored trouble codes and freeze frame data. Also, repair or replace system circuits/connectors as required and retest the system to ensure that repairs were successful.

Common mistakes when diagnosing the P0B74 Code

Here we have listed a few common mistakes that should be avoided while performing the diagnosis:

• A defect in the high voltage battery connection
• An error in the high voltage battery assembly
• Wiring issues in the system