BHPian sandeepmohan recently shared this with other enthusiasts:Rattle from within IRVMFor about 2 years now, I’ve been experiencing an annoying rattle coming from the IRVM. It varies based on weather conditions. The warmer it gets, the more annoying the rattle gets. Minute engine vibrations were enough to set this rattle off and with not so even roads in New Zealand, even the 6 minute drive to work was annoying. I looked everywhere for this issue and did not find anyone reporting this rattle. I thought of replacing the entire IRVM assembly. Its an expensive part. I thought of a used one from a salvage yard and there were many. However, at $200, its still pricey for what it is and I’ll need to go with what they send. Who knows if the mirror they send me is has the same issue, or something else entirely. I found a post on Bimmerpost that discussed swapping out the mirror for a newer one. In one of the responses, one of the members managed to open up the mirror. I followed what they did to pry it open and after a little investigation, managed to identify where the rattle was coming from. I don’t have many pictures so will do my best to explain the source of the issue.Tools required:Trim removal toolFeeler GaugeSmall tipped flat head screw driverSticky Felt padAs you’ll see from pictures, there’s loads of electronics within the mirror. There are some sensors in there and a little light that I’ve never seen lit from below the mirror. Among all the electronics there is a Electronic Toll Card reader fitted inside the mirror. This allows for automatic toll payment on Japanese motorways and incorporates audio visual alerts on the IRVN. There is a credit cars sized slot for the smart card. This was not used anymore on my car. Turns out, this unit was shaking within the mirror, knocking against a plastic support. The mirror assembly was also a little loose.The ProcessTo start the DIY, you need to first remove the plastic housing that surrounds the mirror mount that fuses to the windscreen. This is probably the easiest and fastest job. Putting it back is easy too. A trim tool is all thats needed and the unit snaps off. The mirror on my car is fixed to the windscreen via a sliding mount. Older cars had a twist mechanism. Once the plastic housing is remove, you need to use the small flat head screw driver and release a electronic molex connection. This is the main power source to the IRVM. A little hard to release this connector due to the confined space around the mirror mount. Once this connector is off, you need to hold the entire mirror mount with both hands and gently slide down, in the angle of the windscreen. No excess force. There is some resistance but it does pop out with ease. Once again, refixing it back is also easy and quick. With the mirror now off the windscreen glass mount, I placed it on a flat surface and started feeding in the feeler gauge at the same positions as the Bimmerpost post indicated. It took some time to get it right and I may have spent some time popping the lid off. My goal was to not break any of the plastic hinges that secure the plastic cover. After about a couple of minutes, I managed to get the cover open. This exposed the full inside of the mirror unit, as seen in pictures. A few wire connectors had to be disconnected to make it easier to work on. There are some very fine wires inside that need careful disconnection. Once that was out of the way, I went on a tapping exercise to find out where the rattle was coming from. It didn’t take very long to narrow down the source. It was the ETC card reader + the inside plastic frame securing the mirror. There was some minor play resulting in a annoying rattle. I removed two screws that secure the lid of the ETC card reader to reveal the internal electronics. I was now left with a backlid (No photos unfortunately) that had a screw securing it from behind the mirror. I could not find any way to gain access to this one screw holding this. I had to give up here as I did not want to rip the mirror apart, which was secured with some strong glue of some kind. I knew the source of rattle. Now I had to do a “jugaad” to arrest it. Ideally removing the card reader unit was the correct way but I couldn’t remove it. In the end, I used a 1mm thick double sided felt tape and placed it on both ends of the card reader so it does not move from its place. I also placed a tiny patch of the same tape to ensure the plastic frame within had pushed itself against the back of the mirror so it does not rattle. Shook the IRVM by hand and heard nothing. As the card reader is of no further use, I decided not to power it again. I sealed off the power and data cable with insulation tape. Connected all the other wires that assist with the headlamp and rain sensor. Unsure if this IRVM is auto dimming. Once all this was done, I put back the external IRVM plastic housing. Everything snapped into place with relative ease. Mounting the mirror back to the windscreen mount was a 10 second job. The plastic housing taking another minute. Tops. Started the car, drove around the block. No rattles. I was super thrilled. Drove 400km the next day and no noise or rattle whatsoever. Most pleased with what I did. My only expense here was a feeler gauge at $22, as I did not have one with me. Unfortunately, I did not photo document the entire procedure so this is all I have for pictures. The ETC card reader is the unit with a white label stuck on it. The lid comes of once you remove two small screws. One located on each side. One such screw is visible in the photo. However, there is one screw holding the lower part of the lid thats secured from behind the mirror. I could not find a way to get to it. Check outBHPian commentsfor more insights and information.
