This article gives detailed instructions on replacing the Intelligent Battery Sensor (IBS) in a BMW E60 5 series vehicle. Even though we used a 2006 530xi touring wagon to perform this repair, this article can be applied to any 2004-2010 5 series vehicle with minor modifications to the repair steps.
A BMW E60 battery sensor (IBS) failure can cause a number of electronic malfunctions ultimately leading to a vehicle “no start”.
As many of our readers know, we are very fond of the BMW E60 sedans and E61 touring wagons here at the Repair Guide. In fact, we personally own a 2006 530xi touring wagon which shows up in a lot of our articles (including this one). Unfortunately the E60 series of BMWs have been plagued with electronics issues…many of them stemming from damage to the vehicle’s battery sensor.
The battery sensor, also known as the intelligent battery sensor (or “IBS”) was added to the new BMW E60 5 series in 2004. The introduction of advanced electronics in the new 5 series put a strain on the battery, especially when the vehicle was not running. To prevent the battery from being completely discharged and leaving the driver stranded, BMW added an intelligent battery sensor to monitor the electrical system and insure the battery maintained a sufficient charge to start the vehicle. The IBS (located on the negative terminal of the battery) contains a small microprocessor that continually monitors the battery and makes calculations determining the state of charge and the state of health of your battery. This data is sent to the DME (the BMW’s engine control module) which continually evaluates the condition of your battery and makes adjustments to power consumption as necessary to prolong its life.
All of this works seamlessly…unless you experience an intelligent battery sensor failure. When the IBS fails your vehicle’s power management system can no longer determine the condition of your battery and all hell breaks loose. The first symptoms many owners notice is a power reduction to certain on-board systems…especially consumer electronics like the power seats (unable to “remember” their stored settings) and having to reset the clock ever time the car is started. Owners of all-wheel-drive models have reported their vehicles entering “limp-mode” making them very difficult to steer. Continuing to drive with a failed IBS usually ends up with a control message related to battery discharge and a complete shut down and “no-start” of the car. For those home mechanics with diagnostic scanners, the common fault codes stored in the vehicle’s DME from a faulty intelligent battery sensor are 2E8B, 2E8C and 2E8D…all related to IBS signal or function failure.
The most common causes of IBS failure are mishandling the sensor (exerting unnecessary levels of force on the negative terminal while servicing the battery), incorrect charging or jump starting of the vehicle, or water damage. If you own a BMW E61 touring wagon that has experienced a water leak in the battery compartment due to clogged sunroof drains, there is a very good chance you have damaged your intelligent battery sensor. Please read our article BMW E61 Trunk Leak Sunroof Drain Failure for more information.
If your intelligent battery sensor has failed and you cannot start your vehicle, temporarily disable your IBS by unplugging the DME lead (the blue plug). You will be now be able to resume “normal” operation of your vehicle. Please note – this is not a long term fix. You must still replace your intelligent battery sensor to avoid damage to your battery.
Replacing your intelligent battery sensor is a very straightforward procedure and can be easily done by even the most novice home mechanics. One thing to note is that many of the original intelligent battery sensors were one piece units; the leads for the positive terminal and the DME were “hardwired” into the sensor (see image below). The newer replacement sensors do not have the leads attached…the adapter leads must be purchased separately along with an adapter wire to connect them to the sensor. In a nutshell, you will have to purchase three parts (a sensor, the adapter leads and the adapter wire) in order to complete this repair. We have provided links below for all three parts so you don’t have any issues when ordering.
1. Intelligent battery sensor/adapters (required) – When purchasing a new IBS, you will also need to purchase the adapter wire and leads. The new replacement IBS units do not have the adapter wire and leads attached to them…they must be purchased separately.
- In order to perform a BMW E60 battery sensor replacement, you will need to access your vehicle’s battery compartment in the trunk of the car. The battery is located on the right side of the trunk.
- BMW E60 sedan – remove the right side trunk trim panel (its held in place with a plastic rivet) and storage tray to access the battery as shown below.
- BMW E61 wagon – simply remove the right side hatch and storage tray (held in place with plastic nuts) to access the battery.
- Once you have gained access to your battery, use a 10mm socket wrench to remove the BMW E60 battery sensor from the negative terminal.
- Disconnect the DME and the positive terminal leads from the battery sensor.
- Follow the battery sensor to where it attaches to the frame of the car. Use a 13mm socket wrench to remove the nut securing the battery sensor. Remove the sensor from the vehicle.
- Install the new BMW E60 battery sensor to the frame of the car being very careful not to drop or bump it against anything. DO NOT connect it to the battery yet…only to the frame of the car. Remember the sensor is very fragile and should be handled like its an egg.
- Next, install the new adapter wire to the sensor.
- Install the adapter leads into the adapter wire.
- Reconnect the DME and the positive terminal connectors.
- Carefully install the BMW E60 battery sensor on the negative terminal of the battery as shown below. The mounting nut should be facing up.
- Tighten the mounting nut on the sensor to the negative battery terminal. If you have a low end torque wrench, torque the nut to 5 Nm (3.5 ft-lb). If you don’t have a torque wrench, make sure the nut is snug. DO NOT overtighten…you can shear the mounting bolt off of the sensor.
- Reassemble the vehicle.
- When you first start the vehicle after replacing the sensor, you may have several dashboard and iDrive warning messages appear. This is normal! When the intelligent battery sensor is disconnected it may cause warning messages and lights to appear in your car when reconnected. Drive the car for a minute or so…this will make all of the error lights and messages disappear as the battery sensor resets.