BMW E46 GM5 Module Repair – 30 minutes
The following article gives detailed instructions on repairing the GM5 module in a BMW E46 3 series. Even though we have used a 2003 325ci to perform this repair, this article can be applied to any 1998-2006 E46 3 series vehicle with minor modifications.
A BMW E46 GM5 module repair can help cure erratic door locking, power window malfunctions and windshield wiper system failure.
It is an uncomfortable truth that age is starting to take its toll on many key electronics in our wonderful E46 3 series cars. When we realize that a good portion of the E46s ever produced are now over 20 years old, it becomes easier to understand why systems are starting to fail. Time, environmental conditions, driving habits, poor battery maintenance and improper charging are slowly degrading electronic control modules, often causing an array of malfunctioning systems in their wake.
One of the more notorious electronic controllers known for malfunctioning in the BMW E46 is the GM5 module. The BMW E46 GM5 module (also known as the body control module, general control module or ZKE) directly controls many key systems in the 3 series vehicle including:
- Windshield wipers and washer system
- Central locking system and trunk/tailgate release
- Keyless entry
- Anti-theft system
- Power window control
- Interior lighting
A failing GM5 module can cause many different issues in the BMW E46, but the most popular problem seems to be erratic central door lock operation with the keyless entry (key FOB). Typical symptoms of a GM5 related central locking issue include arbitrary locking and unlocking with the key FOB, usually followed by a complete system shutdown requiring manual operation with the key. The BMW Repair Guide 325ci used in this article would unlock and lock perfectly with the key FOB once or twice, then go into complete disarray requiring disconnection of the battery to reset the system. Repairing the GM5 module completely cured the issue and the car is back to normal.
Whatever issue your BMW E46 GM5 module is creating, the good news is it can easily be rectified by removing the module and having it repaired. The GM5 module is located behind the glove box on the passenger side of the vehicle, and can be removed in about 15 minutes with just a couple of tools. The BMW Repair Guide only recommends shipping your GM5 module to a competent repair shop to have it fixed. We discourage all home mechanics from attempting to fix the GM5 module on their own. There are many fine repair shops online that can be found with a simple Google search…most of them charging about $100 with a 24 hour turn around.
There is no need to purchase a new BMW E46 GM5 module…your damaged module can be easily fixed by shipping it to a reputable repair shop. A simple online Google search will return plenty of options to choose from.
1. Glove box mounting screws (optional) – If you own an E46 that you bought used, we are willing to bet you will be missing some glove box mounting screws. These screws tend to disappear over time…the casualties of prior repairs done by sloppy mechanics.
Screw self tapping 4.9×19 – Genuine BMW 07149156627
2. Glove box flashlight (optional) – Many BMW E46 owners never realize that there is an emergency rechargeable flashlight mounted in their glove box! Over the years, these flashlights lose their ability to charge, or simply disappear. Since you will have to remove the glovebox to do this repair, now is a great time to replace the flashlight.
Flashlight glove box – Genuine BMW 63316962052
3. Lower dashboard light bulb (optional) – Since you will have to disconnect the passenger side lower dashboard lighting to do this repair, now is a great time to replace the bulb. It only takes a minute to replace it, and avoids any future headaches of having to lay on your back to replace it.
Bulb 12V 5W festoon style – Sylvania 63217160805
Screwdriver – phillips
Screwdriver – flat blade
Section 1 – Removing the BMW E46 GM5 module
Removing the GM5 module is a very straightforward procedure. We cannot stress enough the importance of ALWAYS disconnecting the negative terminal of the vehicle’s battery before working on any electronic module in your BMW.
- Before removing the BMW E46 GM5 module, you must disconnect the vehicle’s power. Use a 10mm socket wrench to remove the negative terminal from the battery. Wrap a rag around the terminal to avoid inadvertent contact with the negative cable.
- In order to access the GM5 module, you will need to remove the passenger side glove box. The first step is to detach the door from the side catches by removing the two plastic pins (rivets) with a flat blade screwdriver.
- Remove the five phillips head screws securing the glove box housing to the dashboard.
- Disconnect the three wiring connections from the back of the housing.
- Next, the lower dashboard trim needs to be pulled loose. It is simply held in place with a plastic tab that slides into the plastic module mounting rack. Grab the trim and pull it out, then push it down and out of the way.
- With the lower dash trim out of the way, you can now access the 8mm nut anchoring the bottom of the module rack to the firewall. Use an 8mm nut driver to remove the nut.
- The module mounting rack is anchored at the top by two dashboard hooks that it snaps into.
- To unsnap it from the two dashboard hooks, grasp the top of the mounting rack and push forward (towards firewall).
- Pull the rack down so the GM5 module can be accessed.
- CAREFULLY cut the zip tie around the wiring harness and remove it.
- The GM5 module should be removed from the mounting rack before attempting to disconnect the three wiring harnesses. It is very difficult to remove the harnesses with the GM5 module still in the rack. Start by carefully pulling down on the wiring harnesses to clear them out of the way…there is enough slack to do this now that the zip tie has been removed.
- Grasp the module and pull it free from the mounting rack.
- Remove the first wiring harness by squeezing it and sliding it sideways until it releases from the GM5 module.
- Remove the last two wiring harnesses by raising the white plastic locking mechanisms and pulling the plugs free from the module.
- You can now remove the BMW E46 GM5 module from the vehicle.
Section 2 – Repairing the BMW E46 GM5 module
As discussed at the beginning of this article, we only recommend sending your module to a reputable repair shop that specializes in refurbishing E46 GM5s. Most shops charge about $100 with a 24 hour turnaround. Just run a Google search and you will find plenty of qualified repair shops that will be more than happy to help you out.
BMW E46 GM5 Module Repair Finished
If you have any questions or comments, please feel free to contact us. And congratulations for Doing It Yourself!