I have a Alpine CDA-9811 head unit that worked great until I put it in my friends car for a test. It worked in there, but now I have no output from the speakers in my system. This is from the amplifier that is built into the unit.
I checked the menu and the ams are turned on, I have it on the bench right now to check but do not know were to start looking for the problem.
None of the outputs are working and the heatsink on the back of the unit gets warm (not hot) which makes me think that the amplifiers may be working but in somekind of a mute mode?
Are there internal fuses in this head unit that I can check? I did reset the system. Could there be an issue with the face plate that is causing this? I assume that it is working correctly because it beeps when I go into the setup mode, but, the tuner up and down buttons seem to be acting up (the tuning does not move when I press them)
I cannot afford to buy a new head for my car and this should be an easy fix, but I cannot seem to find schematics on it (less buying from e-bull)
Thanks for your time,
Jeff
I checked the menu and the ams are turned on, I have it on the bench right now to check but do not know were to start looking for the problem.
None of the outputs are working and the heatsink on the back of the unit gets warm (not hot) which makes me think that the amplifiers may be working but in somekind of a mute mode?
Are there internal fuses in this head unit that I can check? I did reset the system. Could there be an issue with the face plate that is causing this? I assume that it is working correctly because it beeps when I go into the setup mode, but, the tuner up and down buttons seem to be acting up (the tuning does not move when I press them)
I cannot afford to buy a new head for my car and this should be an easy fix, but I cannot seem to find schematics on it (less buying from e-bull)
Thanks for your time,
Jeff
If you have a volt meter, set it to the DC volts selection and check from ground to each speaker wire, one at a time of course. You should have about 6 volts on each of the 8 wires. If you have 10 volts on one wire and a volt or 2 on the other 7 wires, you have a bad output chip.
Thanks for the help,
I did the check with my voltmeter and I am getting between 6.18 to 6.20 volts on all of the speaker pins.
Does that rule out the output device?
I did the check with my voltmeter and I am getting between 6.18 to 6.20 volts on all of the speaker pins.
Does that rule out the output device?
Yes that pretty much rules out the chip itself. Go back through the menu and make sure the AMP-IC function is still on. 9815 is AMP-IC, it might have a different name on the 11. Also if the switch on the bottom got switched you may have to unplug the harness or reset the radio.
If none of that works, do you have any way to check the RCA outputs? headphones and a stripped Patch cord? a jam box with AUX input?
If none of that works, do you have any way to check the RCA outputs? headphones and a stripped Patch cord? a jam box with AUX input?
Thanks!
The amp is set to on, I have tried the ai-net switch both ways, reseting the unit each time. I have it running on a modified PC power supply so I can kill the power at any time. I just hooked it up to a old pioneer stereo that i have down here and there is nothing coming out of the front or rear pre-outs.
The amp is set to on, I have tried the ai-net switch both ways, reseting the unit each time. I have it running on a modified PC power supply so I can kill the power at any time. I just hooked it up to a old pioneer stereo that i have down here and there is nothing coming out of the front or rear pre-outs.
Wow... is there a cell phone mute wire that could be somehow grounded, or maybe the amp turn on wire was grounded in your friend's car and caused some kind of internal problem??
any ideas what kind of voltage should be on the pink/black wire? I will check to see if it is shorted to ground.
No idea what voltage is on that wire but I am pretty sure the display reads Interrupt if it is interrupted. Like PPI said check for 12 volts on the remote and power antenna wires.
I checked at least the remote turn on pin when I checked the speaker voltages. there was no voltage on it. Should it be a constatant 12V on these leads?, I was on under the impression that they should have a positive pulse during turn on?
The blue/white wire should have 12volts on it anytime the unit is powered up. The blue wire should have 12 volts on it whenever the tuner is turned on. I am not sure about this radio, but the lack of 12volts on the amp remote wire in some radios means the op-amps are not getting power.
Is there a chance that one of these wires touched ground while putting it in the other car?
Is there a chance that one of these wires touched ground while putting it in the other car?
there is always that possibility. I did not think that it happened, but it might of on the dis-installation. I was not there for that part of it so it may have happened.
The wierd thing is I do not smell anything burnt. Did the magic smoke stay inside this time?
The wierd thing is I do not smell anything burnt. Did the magic smoke stay inside this time?
I just checked it again, the remote turn on and the power antenna lead are at 11v when the head unit is turned on.
I also checked the phone mute line, and when I ran it to ground, 'interrupt' came on the screen.
That was my next step. I will take it apart tomorrow, where do you want me to start checking voltages?
I have a scope over here so that I can take waveforms also. I have a few years in electronics, but have never worked in mobile audio.
I have a scope over here so that I can take waveforms also. I have a few years in electronics, but have never worked in mobile audio.
Remove the CD mechanism, Look around for some 8 pin surface mount ICs there should be several of them with the same numbers on them.
Is that a 4Volt preout unit? If it is it may have negative voltage on pin 4 of the op-amps and the same amount of positive voltage on pin 8.
Is that a 4Volt preout unit? If it is it may have negative voltage on pin 4 of the op-amps and the same amount of positive voltage on pin 8.
The CD mech was a breeze to get out! My gosh I did not think that it would be that easy!.
There are a 2 8 pinners but the 2 that stand out are BA1471F 14 pin quad op amps. They are the only pair that is the same. By the data sheet the power should be on 4 and 11. I get nothing on either to ground.
Am I looking at the right chips?
There are a 2 8 pinners but the 2 that stand out are BA1471F 14 pin quad op amps. They are the only pair that is the same. By the data sheet the power should be on 4 and 11. I get nothing on either to ground.
Am I looking at the right chips?
If according to the datasheet, they are op-amps then yes they are the ones.
Is the unit a 4Volt preout unit? Are the RCA cables Green? Or if they are panel mounted jacks, is there a green ring around the jack?
If yes, on some of those radios had an outboard power supply. A small metal box with what looks like a patch cord going to it. Check the cable going into the box and going into the back of the radio.
Is the unit a 4Volt preout unit? Are the RCA cables Green? Or if they are panel mounted jacks, is there a green ring around the jack?
If yes, on some of those radios had an outboard power supply. A small metal box with what looks like a patch cord going to it. Check the cable going into the box and going into the back of the radio.
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