yurisuika
08-24-2022, 06:38 AM
When I first got an E36 in 2010 I used those cassette adapters with the aux line, but of course those left an annoying wire coming out of the middle of the center console. They were always cheap and the plating on the jack would wear out, so I moved onto the Bluetooth versions, but they had only 4 or 8 hours of playtime and that just sucked, not to mention the quality of going through the tape head was still not great. Several years ago I put some Focal speakers in my car, and the cassette adapters were just not cutting it, so I moved to burning CDs. Sound was pretty great when it didn't cut out when I shifted into 2nd, but a full 90 minute hardcore/jungle DJ tape rip would have to go on 2 CDs and it sucked not being able to utilize my 500GB+ library of mostly FLAC audio on the go like I used to be able to. So, I decided to look into modding the C33. I was adamant about keeping the stock aesthetic, so it was my only option.
Now, there is an option out there for a PnP device called the GROM, but it costs something like $180 and it only is BT 2.1, and the best you get is SBC codec. You lose the CD player in the process, which I guess is not the worst trade off. BlueBus is another option for $200, and although apparently some people have gotten it to work in E36s, it was designed for later models and E36s moved from MBUS to IBUS and I didn't want to wait a long time for delivery for what might not even work for me. I wasn't even sure if it was compatible with a C33, maybe only C43 or CD43, plus I think it only supported SBC as well. There are other options you can find on eBay for like $60 with the same story. Instead, I had a much better idea. I was going to get a setup that not only supported aptX and aptX HD, but also Sony's LDAC codec, which my Xperia phone could utilize, and I would get super high quality Bluetooth audio in my E36.
So, along with your soldering iron of choice, here are all of the components you will need to mod your C33 to be hella awesome.
T-Taps - https://www.amazon.com/dp/B09YGH6FNQ
12VDC Switch - https://www.amazon.com/dp/B07G17HWW8
Female Cigarette Lighter Outlet - https://www.amazon.com/dp/B07T1B52G7
Car Charger Adapter - https://www.amazon.com/dp/B07J6FWK57
TUNAI Firefly LDAC Bluetooth Receiver - https://www.amazon.com/dp/B01HDO66NK
3-Pole TRS 3.5mm Female Plug to Bare Wire - https://www.amazon.com/dp/B09Y17P74W
(Optional) Coiled Braided USB Cable - https://www.amazon.com/dp/B09FGHCRXT
I had very little experience with soldering before this, mostly just mending some wires and for my Renown wheel install with the bypass for the airbag lamp, which later failed anyways so to hell with it. I only had a butane iron, and let me tell you, DO NOT USE A BUTANE IRON to do this job. You will screw up your radio because those things are the complete opposite of temperature stable, plus they shoot a huge jet of hot air out the side. Great if you are trying to fix something out in the boonies, but not for fine work. So, after screwing up my first PCB, I decided instead of trying to bridge the pins with wires I'd just get a used C33 for $30 off of eBay and started fresh. I only needed the cassette module after all, so functionality of the rest of it was not important for me. I got a 60W iron (https://www.amazon.com/dp/B09DSDBC7G) that was temperature adjustable. You only really need 30W of power for the job on a PCB, but having a higher wattage one in which you can limit the temperature will allow it to heat up quicker and maintain that desired temperature more stably. It came with all of the accoutrements, including 0.8mm solder. That worked pretty well, perhaps 0.6mm would have worked better, but 1.0mm would probably be a bit much for this.
Anyways, enough preamble and onto the build. I had to remove the radio, the OBC, and the lower console cubby where the cigarette lighter is located. Removing the radio is simple enough, just loosen the two screws with a Torx (maybe it has to be a Security Torx?) and it should come out easily enough. Be sure you have your radio code written down somewhere. Writing it on the radio is a pretty safe bet. To remove the OBC, you are apparently supposed to press some lever on the bottom side though the circular hole of the cubby, but I always just get a screw driver and push it forward from the back. To get the cubby section out, there are some small tabs that keep it in position on the sides, so gently press outward on the surround to get them to pop out, the one on the left, right, and bottom. I removed the fuse for the cigarette lighter before removing the terminals to that and my ASC button. No heated seats or alarm light or HiFi in my coupe, so you might have a few more wires to remove than me. Be sure to make note of which are which, perhaps attach some painters tape with some labels.
Now, for the install. Starting coming out of the wires for the cigarette lighter, I used some t-taps to get power. In my car, the wires go into some carpet, so just tapping into there was the easiest route for me. I used the 22-18 AWG taps, the red ones. The brown wire is the negative, and the red+black with white dashes one is the positive.
So, you may not know it, but your cigarette lighter is always powered, so you will need a switch to keep it from sucking the life out of your car when it sits. I wanted to go with a stealth build, since a switch for this is kinda lame to be on show, but another option you could go with is a switch from Falk MFG (https://falkmfg.com/collections/interior/products/e36-aux-switch). I found out about them afterwards, but they make both a switch and fast charging USB A/C panels that you could put in next to your ASC switch, if you have room. Alternatively, you could source a Euro switch for the fogs that has a rear fog lamp button, but that is getting a little pricey, and makes wiring it a bit more of a pain. I put a connector to the positive line on one side of the switch and ran it beneath the shifter shroud, so I can toggle it with relative ease and have it completely hidden. The listing on the one I used was sort of all over the place in terms of specs, but it can definitely handle the power. I chose this one because of the form factor of it, including having a wire that came out of the side. It was a nice, compact unit that would fit cleanly below the shroud.
707762
On the other end, I soldered it to the red wire of the second cigarette outlet. I just cut of the ring terminals this one came with. This is easier to do at a table instead of inside the car, so do that before the previous stuff. I wrapped it in electrical tape which I then used the iron to seal, but you could be fancier and go with some actual shrink tubes. Then, the black wire goes into the tap into the brown wire of the stock cigarette lighter. I chose this outlet in part because it had pretty solid 16 AWG wires and a built in 15 Amp fuse.
From there, just plug in your USB car adapter. From the Qualcomm 3.0 port of mine, I ran a nice coiled Type C cable out from the hole in the cubby, so I can charge my phone if I need. It even came with a leather pouch, clasp, and wooden dowel to keep the coils in shape. Talk about fancy.
707769
On the 2.4 Amp port, I put in the Bluetooth receiver. I went with the TUNAI Firefly because it supports LDAC, the best Bluetooth codec that will get you the best audio. As well, it needs to have a 3.5mm out to be able to attach to the C33. It is definitely a quality product and was worth the cost. Something very important that you will need to sort out if you go with a different product is that you WILL need a ground loop isolator, otherwise the engine will make a sound through your speakers that increases in volume and pitch as it goes under more load. The TUNAI has one built in that you can toggle from the device's app. There are also some features like a party mode that I haven't tried out, plus you can change between focusing on bitrate or signal strength. Leave it set to signal strength for this application. It's a powerful device in a sleek, compact form factor.
Anyways, coming out of that is a male 3.5mm TRS connector. It is short, but it comes with an extension cable. At the other end of that, you will attach to the female 3.5mm connector that you will solder into your C33.
707770
To open up the radio, there are two screws on the back that you need to remove to take off the top cover. From there, you will see the cassette module inside. There are four screws on each corner that you need to take out. Now that you have the cassette module out, you need to remove the two screws on the side that hold on a thin metal cover. As well, there are three on the under side of the module that you may need to take out to remove the cover for the belt access. There is a tiny plastic washer that holds in the spindle for one of the gears on this cover. If this goes flying off, you probably don't need it, but why not be careful and keep track of it.
There are two ways you can go about getting the C33 to think there is a cassette always playing. One is to put in a tape without any tape in it. I tried this but I think something else was wrong and I couldn't get it to work at the time, but this is probably the better option if you don't want to have to take the radio out again to regain tape functionality. On the downside, it might be noisier. The other way is to set it so that the mechanism is always in the loaded state. To do this, you will have to take off the spring on the top side of the mechanism. The attached arm is what pushes the cassette in and out of the system, but it also toggles a small black microswitch that detects whether a tape is in or not. We want the arm to always be back, as though a tape is loaded. Use some adhesive tape or glue to hold it securely in the rearward position. To get the mechanism into the downward position as though it has pushed a cassette onto the gear system of the device, we have to take off that bottom cover. You will see a gear on the side that controls it. Move that gear out of its track and get the mechanism in the down position, move the gear back onto its track, and then put the bottom cover back on again.
So, onto the soldering bit. We are going to put the 3.5mm connector wired directly before the preamp of the the device. You will see from where the module connects to the rest of the radio there is a wide and then two narrow traces coming from the outer side of the rear-facing PCB. These are the ground, right channel, and left channel lines, respectively. They come up to some solder blobs where the pins have been bent over. Don't try to solder onto the cable here, as there is a much easier entry point just beyond that. From there, a ribbon sort of wire connects all those pins to the PCB that was covered by that thin piece of metal we took off. You will see here that it has been labelled, from the outside in, once again, Ground, Right, and Left. Here, they have left the pins sticking straight up, so it offers an easier point to solder to, and you won't screw up the solder that was already in place like on the other end of that wire.
707768
With the 3.5mm cable I got, the ground was the black, but for some reason the right channel was the white and the left was the red. I thought it was sort of a standard to have it the other way around, but who am I. Anyways, make sure you check your listing to know what the wires are. Getting the pre-made 3.5mm connector with the decently thick inner wires that were pre-tinned was definitely the way to go. You can run the cable through one of the holes on the right side of the device. I tore up a cable on my first attempt at this trying to run it through the back where the massive IBUS connector goes, but going on the right side is a pretty safe bet. Just be gentle putting the radio back in. Solder it according to matching up the ground, right, and left wires, make sure you are not bridging any of the connections, and you can put it all back in. I put a little bit of electrical tape on the inside of the metal cover to ensure it would not accidentally bridge the exposed portions of the wires. Make sure the pins on the connector to the cassette module are not bent. I thought I had screwed up my solder job when I was not getting any left channel, but one pin was bent out of the way.
Now put it all back together. You can probably stuff some foam inside the tape door to reduce any noise from the motor and gears, although it is really quiet on my system, so I didn't bother. Plus, I just thought of that now, a couple weeks after the fact. If when it runs you hear loud clacking that is abnormal, you probably didn't get the mechanism's gear into the right spot.
Mate the male and female 3.5mm connectors, put the fuse for the cigarette lighter back in, and put all the components back into the console, and put in the code for your C33. When finding a spot where you'd like the hidden cigarette outlet to go, consider where it will have the best signal. I believe I went with to the right of the cubby myself; the lights from the devices inside did not come out from anywhere. This is basically a fancier aux mod, so you could run a 3.5mm TRS splitter to somewhere as well. Perhaps drill out a hole for a female 3.5mm connector in one of those little panels and glue the thing in place, or get that panel from the E90 that has one plus USB, although I think that isn't fast charging. Now you should have an awesome system that beats the hell out of CD audio and has the convenience of having your entire library at your fingertips!
707767
Now, there is an option out there for a PnP device called the GROM, but it costs something like $180 and it only is BT 2.1, and the best you get is SBC codec. You lose the CD player in the process, which I guess is not the worst trade off. BlueBus is another option for $200, and although apparently some people have gotten it to work in E36s, it was designed for later models and E36s moved from MBUS to IBUS and I didn't want to wait a long time for delivery for what might not even work for me. I wasn't even sure if it was compatible with a C33, maybe only C43 or CD43, plus I think it only supported SBC as well. There are other options you can find on eBay for like $60 with the same story. Instead, I had a much better idea. I was going to get a setup that not only supported aptX and aptX HD, but also Sony's LDAC codec, which my Xperia phone could utilize, and I would get super high quality Bluetooth audio in my E36.
So, along with your soldering iron of choice, here are all of the components you will need to mod your C33 to be hella awesome.
T-Taps - https://www.amazon.com/dp/B09YGH6FNQ
12VDC Switch - https://www.amazon.com/dp/B07G17HWW8
Female Cigarette Lighter Outlet - https://www.amazon.com/dp/B07T1B52G7
Car Charger Adapter - https://www.amazon.com/dp/B07J6FWK57
TUNAI Firefly LDAC Bluetooth Receiver - https://www.amazon.com/dp/B01HDO66NK
3-Pole TRS 3.5mm Female Plug to Bare Wire - https://www.amazon.com/dp/B09Y17P74W
(Optional) Coiled Braided USB Cable - https://www.amazon.com/dp/B09FGHCRXT
I had very little experience with soldering before this, mostly just mending some wires and for my Renown wheel install with the bypass for the airbag lamp, which later failed anyways so to hell with it. I only had a butane iron, and let me tell you, DO NOT USE A BUTANE IRON to do this job. You will screw up your radio because those things are the complete opposite of temperature stable, plus they shoot a huge jet of hot air out the side. Great if you are trying to fix something out in the boonies, but not for fine work. So, after screwing up my first PCB, I decided instead of trying to bridge the pins with wires I'd just get a used C33 for $30 off of eBay and started fresh. I only needed the cassette module after all, so functionality of the rest of it was not important for me. I got a 60W iron (https://www.amazon.com/dp/B09DSDBC7G) that was temperature adjustable. You only really need 30W of power for the job on a PCB, but having a higher wattage one in which you can limit the temperature will allow it to heat up quicker and maintain that desired temperature more stably. It came with all of the accoutrements, including 0.8mm solder. That worked pretty well, perhaps 0.6mm would have worked better, but 1.0mm would probably be a bit much for this.
Anyways, enough preamble and onto the build. I had to remove the radio, the OBC, and the lower console cubby where the cigarette lighter is located. Removing the radio is simple enough, just loosen the two screws with a Torx (maybe it has to be a Security Torx?) and it should come out easily enough. Be sure you have your radio code written down somewhere. Writing it on the radio is a pretty safe bet. To remove the OBC, you are apparently supposed to press some lever on the bottom side though the circular hole of the cubby, but I always just get a screw driver and push it forward from the back. To get the cubby section out, there are some small tabs that keep it in position on the sides, so gently press outward on the surround to get them to pop out, the one on the left, right, and bottom. I removed the fuse for the cigarette lighter before removing the terminals to that and my ASC button. No heated seats or alarm light or HiFi in my coupe, so you might have a few more wires to remove than me. Be sure to make note of which are which, perhaps attach some painters tape with some labels.
Now, for the install. Starting coming out of the wires for the cigarette lighter, I used some t-taps to get power. In my car, the wires go into some carpet, so just tapping into there was the easiest route for me. I used the 22-18 AWG taps, the red ones. The brown wire is the negative, and the red+black with white dashes one is the positive.
So, you may not know it, but your cigarette lighter is always powered, so you will need a switch to keep it from sucking the life out of your car when it sits. I wanted to go with a stealth build, since a switch for this is kinda lame to be on show, but another option you could go with is a switch from Falk MFG (https://falkmfg.com/collections/interior/products/e36-aux-switch). I found out about them afterwards, but they make both a switch and fast charging USB A/C panels that you could put in next to your ASC switch, if you have room. Alternatively, you could source a Euro switch for the fogs that has a rear fog lamp button, but that is getting a little pricey, and makes wiring it a bit more of a pain. I put a connector to the positive line on one side of the switch and ran it beneath the shifter shroud, so I can toggle it with relative ease and have it completely hidden. The listing on the one I used was sort of all over the place in terms of specs, but it can definitely handle the power. I chose this one because of the form factor of it, including having a wire that came out of the side. It was a nice, compact unit that would fit cleanly below the shroud.
707762
On the other end, I soldered it to the red wire of the second cigarette outlet. I just cut of the ring terminals this one came with. This is easier to do at a table instead of inside the car, so do that before the previous stuff. I wrapped it in electrical tape which I then used the iron to seal, but you could be fancier and go with some actual shrink tubes. Then, the black wire goes into the tap into the brown wire of the stock cigarette lighter. I chose this outlet in part because it had pretty solid 16 AWG wires and a built in 15 Amp fuse.
From there, just plug in your USB car adapter. From the Qualcomm 3.0 port of mine, I ran a nice coiled Type C cable out from the hole in the cubby, so I can charge my phone if I need. It even came with a leather pouch, clasp, and wooden dowel to keep the coils in shape. Talk about fancy.
707769
On the 2.4 Amp port, I put in the Bluetooth receiver. I went with the TUNAI Firefly because it supports LDAC, the best Bluetooth codec that will get you the best audio. As well, it needs to have a 3.5mm out to be able to attach to the C33. It is definitely a quality product and was worth the cost. Something very important that you will need to sort out if you go with a different product is that you WILL need a ground loop isolator, otherwise the engine will make a sound through your speakers that increases in volume and pitch as it goes under more load. The TUNAI has one built in that you can toggle from the device's app. There are also some features like a party mode that I haven't tried out, plus you can change between focusing on bitrate or signal strength. Leave it set to signal strength for this application. It's a powerful device in a sleek, compact form factor.
Anyways, coming out of that is a male 3.5mm TRS connector. It is short, but it comes with an extension cable. At the other end of that, you will attach to the female 3.5mm connector that you will solder into your C33.
707770
To open up the radio, there are two screws on the back that you need to remove to take off the top cover. From there, you will see the cassette module inside. There are four screws on each corner that you need to take out. Now that you have the cassette module out, you need to remove the two screws on the side that hold on a thin metal cover. As well, there are three on the under side of the module that you may need to take out to remove the cover for the belt access. There is a tiny plastic washer that holds in the spindle for one of the gears on this cover. If this goes flying off, you probably don't need it, but why not be careful and keep track of it.
There are two ways you can go about getting the C33 to think there is a cassette always playing. One is to put in a tape without any tape in it. I tried this but I think something else was wrong and I couldn't get it to work at the time, but this is probably the better option if you don't want to have to take the radio out again to regain tape functionality. On the downside, it might be noisier. The other way is to set it so that the mechanism is always in the loaded state. To do this, you will have to take off the spring on the top side of the mechanism. The attached arm is what pushes the cassette in and out of the system, but it also toggles a small black microswitch that detects whether a tape is in or not. We want the arm to always be back, as though a tape is loaded. Use some adhesive tape or glue to hold it securely in the rearward position. To get the mechanism into the downward position as though it has pushed a cassette onto the gear system of the device, we have to take off that bottom cover. You will see a gear on the side that controls it. Move that gear out of its track and get the mechanism in the down position, move the gear back onto its track, and then put the bottom cover back on again.
So, onto the soldering bit. We are going to put the 3.5mm connector wired directly before the preamp of the the device. You will see from where the module connects to the rest of the radio there is a wide and then two narrow traces coming from the outer side of the rear-facing PCB. These are the ground, right channel, and left channel lines, respectively. They come up to some solder blobs where the pins have been bent over. Don't try to solder onto the cable here, as there is a much easier entry point just beyond that. From there, a ribbon sort of wire connects all those pins to the PCB that was covered by that thin piece of metal we took off. You will see here that it has been labelled, from the outside in, once again, Ground, Right, and Left. Here, they have left the pins sticking straight up, so it offers an easier point to solder to, and you won't screw up the solder that was already in place like on the other end of that wire.
707768
With the 3.5mm cable I got, the ground was the black, but for some reason the right channel was the white and the left was the red. I thought it was sort of a standard to have it the other way around, but who am I. Anyways, make sure you check your listing to know what the wires are. Getting the pre-made 3.5mm connector with the decently thick inner wires that were pre-tinned was definitely the way to go. You can run the cable through one of the holes on the right side of the device. I tore up a cable on my first attempt at this trying to run it through the back where the massive IBUS connector goes, but going on the right side is a pretty safe bet. Just be gentle putting the radio back in. Solder it according to matching up the ground, right, and left wires, make sure you are not bridging any of the connections, and you can put it all back in. I put a little bit of electrical tape on the inside of the metal cover to ensure it would not accidentally bridge the exposed portions of the wires. Make sure the pins on the connector to the cassette module are not bent. I thought I had screwed up my solder job when I was not getting any left channel, but one pin was bent out of the way.
Now put it all back together. You can probably stuff some foam inside the tape door to reduce any noise from the motor and gears, although it is really quiet on my system, so I didn't bother. Plus, I just thought of that now, a couple weeks after the fact. If when it runs you hear loud clacking that is abnormal, you probably didn't get the mechanism's gear into the right spot.
Mate the male and female 3.5mm connectors, put the fuse for the cigarette lighter back in, and put all the components back into the console, and put in the code for your C33. When finding a spot where you'd like the hidden cigarette outlet to go, consider where it will have the best signal. I believe I went with to the right of the cubby myself; the lights from the devices inside did not come out from anywhere. This is basically a fancier aux mod, so you could run a 3.5mm TRS splitter to somewhere as well. Perhaps drill out a hole for a female 3.5mm connector in one of those little panels and glue the thing in place, or get that panel from the E90 that has one plus USB, although I think that isn't fast charging. Now you should have an awesome system that beats the hell out of CD audio and has the convenience of having your entire library at your fingertips!
707767