Garrett Powered Posted August 29, 2012 Report Share Posted August 29, 2012 I was going to record it with my camcorder or something but never got around to it yet Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 29, 2012 Author Report Share Posted August 29, 2012 Finished the wiring for my AUX IN jack tonight. I must have messed something up though because now the entire cassette/equalizer/AUX module does not work... the EQ does not even light up. I get a constant static though the speakers, whether or not the radio is even on, as long as the cassette module is plugged in. The scary part is that the static did not stop when I turned the ignition off... I had to unplug the module from the car before it stopped! YIKES! WTF?! So clearly something is not right, I will have to double check my wiring and all internal plug connections and do some troubleshooting tomorrow. It's almost as if the power to the module is being intercepted and sent through the speakers... that does not make any sense though... Interestingly the switch seems to work fine. Toggling the switch turned the radio on and off as expected. I did not try hooking up any audio to the jack, gotta figure out what I broke first. Here are some pics though. Here is the cassette module with the faceplate removed. Here is the jack... soldering the wires to it was annoying. Here is the module after the jack and the switch were wired in. It looks like like a total rats nest hackjob... It's not as bad as it looks though. Just no way to prevent the wires from going every which way. Sure looks nice on the outside though!! I hope I can figure out what I screwed up. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted August 29, 2012 Report Share Posted August 29, 2012 methinks you may have jumped into the wrong circuits. Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 29, 2012 Author Report Share Posted August 29, 2012 methinks you may have jumped into the wrong circuits. That would make sense... but they should have been the correct circuits, unless the FSM lied to me... but the switch is wired right, so that indicates I at least mapped out the schematic correctly. Whether or not I followed my own schematic correctly is something I need to double check though. My gut instinct thinks I may just have something shorting or grounding out to something it shouldn't... at least that is the easiest thing to check. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted August 29, 2012 Report Share Posted August 29, 2012 easy way is to look for the magic smoke, but by the time you see it, it's too late. Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 29, 2012 Author Report Share Posted August 29, 2012 No doubt! I did not see any magic smoke when I tested last night... so either that's not my problem or I removed power before I destroyed anything. Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 29, 2012 Author Report Share Posted August 29, 2012 Not that I should be reading schematics at work... but I wonder if I nicked my heat shrink or something and have one of the +12v leads on the switch shorting out to the case. That might explain everything... Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 30, 2012 Author Report Share Posted August 30, 2012 OK, well now I'm really confused. Checked out my AUX IN wiring, and it appears everything is hooked in correctly. I also figured out that the static I am getting is unrelated to anything I have done... it's the 23 year old amp going bad, I just never noticed it before because I've never actually listened to the radio. The few times I've had it on I just attributed the static to having no antenna. Looking into my options for fixing/replacing that amp... In the meantime, my wiring is further confirmed. I hooked my ipod to the unit and it worked. Flipping the switch toggled between ipod and radio flawlessly. So both the jack and the switch are wired properly as per the instructions I followed. Two problems though... presumably related? Firstly... with the car off and the key removed and everything, if I flip the switch to "radio" it turns on the amp in the glovebox!! WTF? If I flip the switch back to AUX then it turns the amp off again. Clearly it should not be doing this... Secondly, neither the EQ or the Cassette module are getting any power. No clue why that is... they should be getting power still... Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 30, 2012 Author Report Share Posted August 30, 2012 Just had a brainstorm, so this is basically a reminder for myself when I get home tonight... Maybe it will work better if I remove the "radio trigger lead" from the DPDT switch and reconnect the cut ends together... I suppose if I am getting the power from the amp unit into the tape unit, and it is also sending the "radio on" signal from the amp unit to the tape unit... I suppose it could be messing things up to send power back into the amp via the "radio on" signal. Or something. So... I will try only having the +12v and the "tape on trigger" connected to the switch, so it's effectively a DPST switch. Seems that would at least solve the "can turn the amp on when the car is off" problem... maybe... Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted August 30, 2012 Report Share Posted August 30, 2012 had to dig back to page 33 since alldata doesn't show the 3 piece radio diagrams.... if you're able to turn on the amp with the radio off, i'd say that wherever you grabbed one of the circuits, it was a constant +12V source. if you had hooked into a switched +12V source, it wouldn't be possible. the lack of power to the equalizer/casette.... you may have to undo some stuff circuit by circuit to figure that one out. Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 30, 2012 Author Report Share Posted August 30, 2012 Yeah, it's safe to say that I have some serious probing to do... clearly the 3-piece units are both exactly the same and sort of different that the one piece units. Clearly the +12 I tapped into is a constant power. There is no switched power, unless the "radio on power input" is actually the switched power I should have tapped into instead... either way I clearly did not hook it up quite right. At least I have a couple of configurations to test out now. Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 31, 2012 Author Report Share Posted August 31, 2012 Managed to score a digital copy of most of the 1990 radio service manual... appears to include schematics for the Radio Head and the Amp, which is cool. However for the tape/eq unit, aka the schematic I actually need, it refers me to publication "27D-1989-3 FA", which I cannot seem to acquire digitally. So much for informed poking and prodding... I guess it's back to guess and check. At least I'm learning a lot with this seemingly simple project. Quote Link to comment Share on other sites More sharing options...
ManicMechanic Posted August 31, 2012 Report Share Posted August 31, 2012 Any chance you can send me that schematic sir? Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 31, 2012 Author Report Share Posted August 31, 2012 Any chance you can send me that schematic sir? Absolutely! You can grab it from this link: http://wikisend.com/download/703402/Delco_1990_Auto_Radio_series.pdf Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 31, 2012 Author Report Share Posted August 31, 2012 Well, I think I may have found my problem. Either my switch is defective, or my understanding of electronics is even worse than I thought... So I wired the DPDT switch as per the instructions I found... like so: 1 & 6 are connected to the "Radio Signal Wire" 2 & 5 are connected to "Power" 3 & 4 are connected to "Cassette Signal Wire" The idea is that you connect the power line to whichever function you want, radio or aux, obviously. The problem I am having is that electricity is not flowing through the switch...probing with a multimeter and toggling the switch appropriately I can make a circuit with 2-1, 5-6, 2-3, 4-5. This part is as expected. However the logic probe will not give me 1-6, 2-5 or 3-4 as complete circuits. I would expect that 2-5 would always be a complete circuit... and the break there surely explains why my EQ is getting no power. I would similarly expect 1-6 and 3-4 to be completed when the switch is in the right position. Shouldn't there be an internal jumper between the 2 halves of the switch? As it is the power is coming from the amp, into the switch (never making it to the EQ unit) and either going back into the amp through the tape on lead (like it should, actually), or going back into the amp via the radio on lead which apparently mimicks the signal of the actual radio head unit enough to actually turn the amp on and off. So... do I just need a new switch, or did I make some sort of rookie mistake that I don't know about? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted August 31, 2012 Report Share Posted August 31, 2012 DPDT switch? that would imply that it only switches two circuits and has 3 positions... Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 31, 2012 Author Report Share Posted August 31, 2012 According to everything I've read about how to wire a switch to go between Radio/Aux it calls for a DPDT switch wired exactly how I wired it... so it's supposed to work. Here is a link that features another, vaguely similar use of a DPDT switch... http://www.krisbarrett.com/2009/10/22/audio-output-selector/ Edit: Also, there are 2 varieties of DPDT... on-on and on-off-on Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 31, 2012 Author Report Share Posted August 31, 2012 Now I really wish I had that schematic of the EQ. However it's official that however appropriate a DPDT switch is in some Delco Aux In applications... it's not the right tool for this job. I bridged the power wires and tried the radio in the car again. With the switch set to AUX I get the same results as before... the audio comes through correctly, but the EQ does not get power. With the switch set to Radio I finally get power to the EQ, but the radio sound never makes it to the speakers... also I can still turn the amp on with the car off. Obviously I need to ditch the switch I have and reconnect the Power, Radio and Tape wires that I severed in the first place. My new thought is that I may just need to put a switched jumper wire between the power and tape lines. I'll have to try that next. As a sidenote, this forum is great... I'm usually absolutely terrible about taking notes, but I just realized I've been using this thread as a notebook this whole time. Winner. Quote Link to comment Share on other sites More sharing options...
ManicMechanic Posted August 31, 2012 Report Share Posted August 31, 2012 Thank you for the Schematics... Tomorrow or later this weekend, I'll rip my van apart and show you how I did it. Quote Link to comment Share on other sites More sharing options...
Penglii Posted August 31, 2012 Author Report Share Posted August 31, 2012 Thank you for the Schematics... Tomorrow or later this weekend, I'll rip my van apart and show you how I did it. You are most welcome. The actual AUX IN jack works flawlessly... and of course without the switch installed, putting a cassette into the deck switches things as expected. So the only part I'm having any issues understanding is the switch - which is a significantly less well documented addition. Especially for these 3 piece units. I'm out of town until Sunday evening, but I have all day Monday to muck around with that. I think I'm very close to figuring it out. Quote Link to comment Share on other sites More sharing options...
Penglii Posted September 4, 2012 Author Report Share Posted September 4, 2012 Finally got the AUX IN figured out. Turns out the problems I had were partly my fault and partly the cassette units fault. My problem was not wiring the switch correctly... turns out all I need to switch back and forth between radio and aux is a simple switched jumper between the "tape wire" and the "power wire". The reason I was able to get sound out of the unit, or power into the unit but not both was the cassette module's fault. There must be a bad wire or a broken circuitboard trace or something, because when I unplug the cassette module from the rest of the EQ module it completely solved that problem. Oh well, I don't need to play cassettes anyway. Maybe I'll run across a spare EQ module someday that I can scavange the cassette parts from. Currently the sound from the AUX jack is not very good... all treble and absolutely no bass. It's so much worse than even working cassette units playing a cassette sound that I assume the poor sound quality is related to the bad amp. I'll find that out for sure in a few weeks when ManicMechanic gets me a replacement reciever/amp unit. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted September 4, 2012 Report Share Posted September 4, 2012 even with an aftermarket unit that has aux built in, lower frequency always seems to need some tweaking from what i've experienced. it may be your amp though. i've got two headunits with aux input, one from ~1996, the other from ~2010, i'm used to using the 1996 version, so maybe things have changed since then. Quote Link to comment Share on other sites More sharing options...
Penglii Posted September 4, 2012 Author Report Share Posted September 4, 2012 I suspect the major problem is the amp, It's undoubtedly shot. If the bass is still a bit low after the new amp goes in... that's what the EQ is for. Quote Link to comment Share on other sites More sharing options...
Penglii Posted September 5, 2012 Author Report Share Posted September 5, 2012 Well now, the saga of modding my radio has taken another interesting turn... First, I finally realized that I never reconnected the plug going to the radio head unit that supplies light to the buttons and that supplies the SWRC signal. Hooked that up, and even more bizzare behavior rears it's head. Apparently, even with the car off, jumping the Power wire and the Tape On Input wire will turn on all of the interior backlighting. Say whaaaaaat? Also, now anytime I turn on the headlights the radio signal is shut off. Everything still works, but the radio signal is switched off just like if a blank tape were inserted. I think I am not going to get any further with this AUX IN project until I get a schematic for the EQ module... I really need to see how the circuits are actually linked together in this module. Quote Link to comment Share on other sites More sharing options...
Penglii Posted September 7, 2012 Author Report Share Posted September 7, 2012 YAY!!! Finally got an actual solid motor mount to put in the TGP! Third time is the charm I guess. Quote Link to comment Share on other sites More sharing options...
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