l2bengtrek Posted July 9, 2015 Report Posted July 9, 2015 Hello all! I've been searching for a while and can't seem to find what I'm looking for. Hoping somebody has some wiring diagrams. I have a 94 Cutlass convertible that I did a stereo upgrade to last summer. Kenwood head unit, speakers, under-seat sub and a SWC interface. After failure to get a PAC interface to program, I found that as far as PAC goes, I had THE ONE OF TWO Kenwood model Head units that PAC is having problems making a compatible interface for. After EXTENSIVE research and emails with PAC's tech support, I could only get their CP5 interface to program the climate controls. I originally tried their SWI-RC, which had the same result. They were confident that the CP5 would program to the radio, but it did not. As far as the audio controls went, both parties were up in arms over it and I gave up and settled for just having use of the climate controls. Fast forward to this week, when I decided to take a chance on a Metra Access ASWC-1 to see if it would work. It programmed to the Kenwood in minutes! YAY! Here's the problem, it has no provision for the climate controls! Their tech support confirmed it. So here's my question: Is it possible to somehow by-pass needing an aftermarket interface for the climate controls? I tried using the PAC for the climate controls and the Metra for the audio. It would not work because evidently the audio AND climate control wires need to be hooked up to the PAC to work. I still have the OE 7 pin harness connector intact with the dash harness, I just snipped the audio and CC control wires off. Can I somehow splice the CC control wire back to something in the dash harness to regain the climate controls? Both audio and climate control wires ran into the 7 pin connector plugging into the OE radio. Sorry for the lengthy post..just wanted to give the background of my problem. Thanks! Quote
jman093 Posted July 9, 2015 Report Posted July 9, 2015 The same wire feeds the multiplexed signal for both the climate and radio switches. They all ultimately feed into the radio. The radio communicates this to the HVAC control head over a separate data bus line. How exactly do these interfaces work? My assumption is the different mutiplexed resistance values are programmed to the different various functions and the interface translates this into something the Kenwood unit likes. I do not see how SWRC climate controls could have worked without a factory radio to communicate on the E&C data bus. Quote
l2bengtrek Posted July 9, 2015 Author Report Posted July 9, 2015 The same wire feeds the multiplexed signal for both the climate and radio switches. They all ultimately feed into the radio. The radio communicates this to the HVAC control head over a separate data bus line. How exactly do these interfaces work? My assumption is the different mutiplexed resistance values are programmed to the different various functions and the interface translates this into something the Kenwood unit likes. I do not see how SWRC climate controls could have worked without a factory radio to communicate on the E&C data bus. Thanks Jesse. I'm confused though because there are TWO wires coming out of the 7 pin connector in the radio compartment. One is for the audio signals, the other for the CC signals. The PAC interface had wires in it's harness to connect BOTH wires to. Now the Metra interface, according to their tech support, doesn't have a wire designated to connect to the now open CC wire. Does that make sense? I'm looking to connect this wire back to something to enable the climate controls again. I'm asking if there's something in the dash harness I can jump this wire to now...ore anything I can do. Thanks! Quote
vipmiller803 Posted July 9, 2015 Report Posted July 9, 2015 (edited) It programmed to the Kenwood in minutes! YAY! Here's the problem, it has no provision for the climate controls! Their tech support confirmed it. So here's my question: Is it possible to somehow by-pass needing an aftermarket interface for the climate controls? I tried using the PAC for the climate controls and the Metra for the audio. It would not work because evidently the audio AND climate control wires need to be hooked up to the PAC to work. I still have the OE 7 pin harness connector intact with the dash harness, I just snipped the audio and CC control wires off. If I am understanding this correctly, you are saying that you tried to connect both adapters, but the hurdle was that there is a wire overlap between the adapters. Can you connect the radio wire to the Metra Access unit the same way as when it worked AND connect the PAC unit the same way as when it worked for the climate controls? That would obviously require some splicing and soldering in order to have at least one wire shared between the adapters. Even if you had to make a "Y" for all 7 pins, it would still be doable. I have a feeling that the adapters have a high enough input impedance that it might work, especially if they are programmed while both are hooked up, meaning the distinct final impedances are recognized as normal. With that in mind, I would assume that any simultaneous button presses might throw those adapters off, but that would be something to live with. Edited July 9, 2015 by vipmiller803 Quote
l2bengtrek Posted July 9, 2015 Author Report Posted July 9, 2015 If I am understanding this correctly, you are saying that you tried to connect both adapters, but the hurdle was that there is a wire overlap between the adapters. Can you connect the radio wire to the Metra Access unit the same way as when it worked AND connect the PAC unit the same way as when it worked for the climate controls? That would obviously require some splicing and soldering in order to have at least one wire shared between the adapters. Even if you had to make a "Y" for all 7 pins, it would still be doable. I have a feeling that the adapters have a high enough input impedance that it might work, especially if they are programmed while both are hooked up, meaning the distinct final impedances are recognized as normal. With that in mind, I would assume that any simultaneous button presses might throw those adapters off, but that would be something to live with. I was thinking that way too. I thought use the PAC for the climate controls, use the METRA for the audio controls. Simple right? Here's what happens...when I disconnected the AUDIO wire from the PAC to connect it to the METRA...the climate controls stopped working. So evidently the PAC needs BOTH of the wires to be connected. I confirmed that. When I connected the audio wire BACK to the PAC, the climate controls came right back. I then tried temporarily twisting the audio control wire to both interface wires and I guess they interfere with each other because I couldn't get a response from the METRA. When I disconnect the PAC from this mix, the Metra starts working again. If theres a way to have the PAC control the CC's and the METRA control the audio, I'm fine with that....But any suggestions on what I can do to isolate the two interfaces if they have to share the audio wire? Thanks for the feedback! Quote
l2bengtrek Posted July 9, 2015 Author Report Posted July 9, 2015 Oh, I did want to mention....The PAC was already programmed and had been functioning for the past year...and then I added the METRA. Are you suggesting RE-PROGRAMMING both interfaces after connecting them? Quote
vipmiller803 Posted July 9, 2015 Report Posted July 9, 2015 (edited) Oh, I did want to mention....The PAC was already programmed and had been functioning for the past year...and then I added the METRA. Are you suggesting RE-PROGRAMMING both interfaces after connecting them? I suggest that you connect the PAC to all the wires it was connected to when it worked, connect the Metra to all the wires it was connected to when it worked (yes, there are some wire overlaps, connect them both to those), and then program them both, skipping the functions they cannot handle (most notably, the audio on the PAC unit). I cannot confirm that this will work as I have only tried one adapter at a time before, but it might, assuming the adapters have high enough input impedances. I then tried temporarily twisting the audio control wire to both interface wires and I guess they interfere with each other because I couldn't get a response from the METRA. When I disconnect the PAC from this mix, the Metra starts working again. If theres a way to have the PAC control the CC's and the METRA control the audio, I'm fine with that....But any suggestions on what I can do to isolate the two interfaces if they have to share the audio wire? Thanks for the feedback! Oops missed that just now. Besides reprogramming them while they are both connected, I would think that there would have to be some significant switching element that sends the signal to the right adapter based on audio vs CC. At that point it would be easier to get another HU that works with your PAC. Edited July 9, 2015 by vipmiller803 added on Quote
l2bengtrek Posted July 9, 2015 Author Report Posted July 9, 2015 At that point it would be easier to get another HU that works with your PAC. (Sigh) Agreed... Quote
vipmiller803 Posted July 9, 2015 Report Posted July 9, 2015 (Sigh) Agreed... Well if reprogramming while both are on fails and you do go that route, it could be not too bad, besides the price to pay for a HU for the second time I guess. One thing to keep in mind is that JVC and Kenwood use the same connectors, and there are tons of those units that will fit. When I got my car, it had a kenwood unit that was not compatible with SWC at all. It also lit up the wrong color for the dash and its CD player did not work. I ended up replacing it with a JVC unit that did everything I wanted and only had to switch two pins from the new connector to the old. I was sure I would have to mess with all that wiring, but it was surprisingly simple. One PAC adapter later and some more mangling of connector pins, this time on the car side of the existing adapter wiring, and my steering wheel buttons now work too. Of course, I do not have CC buttons so that made it less of a headache. Quote
l2bengtrek Posted July 9, 2015 Author Report Posted July 9, 2015 Well if reprogramming while both are on fails and you do go that route, it could be not too bad, besides the price to pay for a HU for the second time I guess. One thing to keep in mind is that JVC and Kenwood use the same connectors, and there are tons of those units that will fit. When I got my car, it had a kenwood unit that was not compatible with SWC at all. It also lit up the wrong color for the dash and its CD player did not work. I ended up replacing it with a JVC unit that did everything I wanted and only had to switch two pins from the new connector to the old. I was sure I would have to mess with all that wiring, but it was surprisingly simple. One PAC adapter later and some more mangling of connector pins, this time on the car side of the existing adapter wiring, and my steering wheel buttons now work too. Of course, I do not have CC buttons so that made it less of a headache. Thanks for the info! Think I'm going to give my "buddy" at PAC a call to see if these things can just be programmed for the CC functions. That would be my "less of a headache".. Quote
vipmiller803 Posted July 9, 2015 Report Posted July 9, 2015 Thanks for the info! Think I'm going to give my "buddy" at PAC a call to see if these things can just be programmed for the CC functions. That would be my "less of a headache".. Buddy. Hah. IIRC, you can just click the side button to skip to the next function while you program. In this case, you would skip every single audio function... Quote
l2bengtrek Posted July 9, 2015 Author Report Posted July 9, 2015 True...I just got done e-mailing the fella I dealt with at PAC, we'll see what he says. Thanks!! I am thinking...maybe it needs to be reset back to factory default to start fresh? Maybe the current programing is looking for audio control signals and since the audio wire is disconnected, it disables it? YEAH! THAT'S IT!! LOL Quote
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