i was raeding this and i think it would be safe to just add and on off switch and just turn on the avic after the car is on.. if no harm comes from this reboot then just live with it.. a battery pack should need a switch to not over charge..
i was raeding this and i think it would be safe to just add and on off switch and just turn on the avic after the car is on.. if no harm comes from this reboot then just live with it.. a battery pack should need a switch to not over charge..
The resistor limits the charging current to what is allowed continuously by the battery pack. It won't over-charge.
I'm not sure about the reboots not being dangerous. Many people on this forum have had flash corruption problems. Flash can be corrupted when power fails (or falls too low) while the flash is being written. This is one of the two main reasons I did this.
Hey Joe,
Excellent PDF electrical diagram. If I knew what all that meant I'd just go out and do this. Any chance you can post the parts list. I see on the diagram:
SPD10s30 x2 Diode
R1 resistor 10.0 Ohm 10.0 w
R2, R3 (same size resistor) 1000.0 Ohn .25w
Q1 2N4401
Q2 2N4403
C1 capacitor 10uF 25v
C2 capacitor 100uF 25v
Battery x10 500mA/hr NiCd
they do make someting called a power tamer my current job is building and modifying police, emergency, and federal vehicles. what this does is once you turn the key on the power tamer is activated and when you turn off the car the timer starts and you can set it from 30 min. to 4 hours. so the output side of the power tamer can hook up to the ignition wire of avic and you cap off the ign. on the car side. you can hook up variuos other after market electronics this device. on the cars i do the power tamer is running our custom fuse panels by turning on and leaving on a 150 amp military grade electronic relay for certain amount of time.
there are two power wires at almost every ignition switch in cars. one the accessory in most vehicles loses power during crank. the other which is actually an ignition wire remains at 12v during crank. instead of wiring relays, just run a fused wire to the ign switch and find the wire that maintains power during crank. i appreciate relays and diodes, but fuse holders and 18-14 ga wire is less expensive.
there are two power wires at almost every ignition switch in cars. one the accessory in most vehicles loses power during crank. the other which is actually an ignition wire remains at 12v during crank. instead of wiring relays, just run a fused wire to the ign switch and find the wire that maintains power during crank. i appreciate relays and diodes, but fuse holders and 18-14 ga wire is less expensive.
You're still missing the main problem here. Most car's voltage will drop below 10.5V during cranking. The AVIC shuts down if the voltage goes below 10.5V, even for an instant. My accessory lead maintains power during cranking, but the voltage falls to 10.0V or so, therefore a reserve battery or a "power tamer" is required.
yes thank you JOE KNOWS WHAT A POWER TAMER IS
Hey Joe,
Excellent PDF electrical diagram. If I knew what all that meant I'd just go out and do this. Any chance you can post the parts list. I see on the diagram:
SPD10s30 x2 Diode
R1 resistor 10.0 Ohm 10.0 w
R2, R3 (same size resistor) 1000.0 Ohn .25w
Q1 2N4401
Q2 2N4403
C1 capacitor 10uF 25v
C2 capacitor 100uF 25v
Battery x10 500mA/hr NiCd
You should be able to find it all at www.digikey.com
Interesting site, but not very useful. I would need to order 1200 of some of these parts to place an order.
Any chance of getting some simple pictures of the batteries, battery holder, diodes, capacitor, etc? That would make it super easy to put this thing together.
If somebody can get me a good working parts list I'll build one on a bench and make a video or picture How-to for the site.
Steve
Interesting site, but not very useful. I would need to order 1200 of some of these parts to place an order.
Any chance of getting some simple pictures of the batteries, battery holder, diodes, capacitor, etc? That would make it super easy to put this thing together.
If somebody can get me a good working parts list I'll build one on a bench and make a video or picture How-to for the site.
Steve
This site is pretty useful for ordering electronic components. You can order them in any quantity. The larger the quantity the better the discount. Just be careful not to order any component that is not stocked as the delivery time could take as long as 5 weeks.
If you don't want to order online then you can walk into your neighborhood Radio Shack and pick up all necessary components or similar.
As an example here is a link to a battery holder I purchased from Radio Shack.
Battery Holder
i think they would have it all
if you're not concerned with the power surge that may occur during cranking, why not just change the acc line? instead of using the acc wire in the stock harness, just run a line to the vehicles ignition line? ign remains powered while cranking..
I tried this myself at one point but found out that the +12V constant also experience a dip during cranking.
if your voltage is dipping that low during crank, you might want to get your electrical system checked.. starters draw a fair amount of current, but it shouldn't be enough to dip things that low unless you've got a bad cell or two in your battery.
The allowable voltage range for the Pioneer is 10.8V to 15.1V. Considering I have a 12V battery that only allows me a drop of 1.2V during cranking, quite tight. I think the problem is this tight tolerance not the electrical system in my car. If it is the electrical system in my car then it is highly contagious since several members in this forum are also reporting this problem.
Nonetheless, I've resolved this issue with the circuitry posted in this thread. My comments were only intended to be helpful to the starter of this thread not to start this debate all over again.
oh i'm not looking to start an argument either.. i'm just approaching the problem from a different angle.
first, if your battery is testing at 12v it is bad.. a standard issue car battery should read at 12.6v (there are 6 2.1v cells inside) so that bumps your threshold to 1.8v.. not a lot, but it helps.
as for turning over the starter, one big thing you can do is to reduce the resistance in the system.. think "big 3" upgrade step 2. standard big three is as follows..
larger guage cable from alternator to battery
larger guage cable from chassis ground to battery
larger guage cable from engine ground to chassis ground
this helps the alternator perform to it's full potential by giving more 'room' for current flow. not only will your stereo benefit from the increased available power, but the car usually runs a bit better as well. to help take it a step farther, you can also upgrade a few other things as well.
larger guage cable from starter to battery
larger guage cable from main fuse box to battery
i've done these upgrades in most of my cars, and have always noticed a positive response in just overall car/system performance. my current ride ( 06 mits raider w/ 4.7l v8 ) has a voltage guage tucked behind one of the air vents and watching the thing during crank it vary rarely dips below 11.4v or so. but as always YRMV..
Thanks Joe. I installed a variation of your circuit today and it works great. I used a small, 1.2AH lead-acid battery, mosfets, and added a capacitor at the input of the second mosfet that keeps it turned on for 6 seconds since my car's signal turns off during starting.
is it possible to have the unit turn on once it sees 13 volts? (So after the car has started?) or just ingeneral, to skip the issue with the battery voltage dropping by haveing it turn on after the car has started? Say 8 seconds after the Key is turned to "Run"?
is it possible to have the unit turn on once it sees 13 volts? (So after the car has started?) or just ingeneral, to skip the issue with the battery voltage dropping by haveing it turn on after the car has started? Say 8 seconds after the Key is turned to "Run"?
Yes, a circuit to do either of those suggestions would not be too hard to do.
WOuldn't that solve the problem most of you are having then? (or assume you are creating by the quick on off cycleing of the "computer" in the unit?)
Does anyone know if a device similar to Joe's diagram is available for sale off the shelf? I'd really like to install one of these in my car, but without detailed directions on parts and construction I'm sure I'd just screw it up. 
Back when I first installed my F90BT, I tried to go the capacitor/diode/relay route using this diagram put together like this, but unfortunately the caps weren't big enough and the voltage still drops below the AVIC's threshold.
Now that 3.0 is just around the corner, I'd like to get this working so I won't restart the radio each time I stop at a gas station, etc.
Any help that anyone can provide would be appreciated.
Thanks!
Damn i'm having this same issue in my mk4 golf, i'd also like to know if there is an "off the shelf" option to sort this as it is really bugging me that the unit resets when i start the engine 
Back when I first installed my F90BT, I tried to go the capacitor/diode/relay route using this diagram put together like this, but unfortunately the caps weren't big enough and the voltage still drops below the AVIC's threshold.
The capacitor is too small. In the picture i see a capacitor of 470 uF, that gives you a delay of 0.1 second before voltage drop. In the diagramm it showd 10.000 uF, this should hold around 2.5 seconds (assuming 12V and 50 mA for the relay).
But i don't know if the install help you, that depends on your car. If your car switch off the power for AVIC while cranking then this circuit might help to get power from another "all time hot" source. But if the voltage in your car drop below 10.x Volt cause the starter sucks too much energy then the circuit is useless.
Hi!
I ran into the same problems (rebooting when engine is started) with my new F910BT (european model). I am thinking of fixing this with Joe's original schematic (avic.pdf) but I have some additional questions and I kindly ask the specialists here for help.
1. Putting a fuse into the NiCd Battery plus is of course a wise idea. How many amperes should such a fuse be? Someone within this thread said that the AVIC takes up to 10 amps during operation, so should that be a 10 amp fuse or less?
2. Just to be sure I understand the schematic correctly: When the AVIC runs under normal operation does it pull its current from the yellow constant power line? Is this correct? Otherwise if it pulls its current from the read ACC line then this would mean that all the current has to be sourced through Q1 transistor (up to 10 amps?). Do I understand this correct?
3. I assume the diodes should be of Schottky type - correct? Here in Austria I could get MBR1645 schottky diodes (45 Volt, 16 Amps), can I use this type and do they need some heat sink? Do the transistors need a heat sink (mainly Q1)?
4. Someone up in this thread said, that charging the NiCd cells will only take place when the engine runs. If I correctly understand the schematic (avic.pdf) I cannot see this feature. The cells are connected to CAR_CONST_PWR via the 10 Ohm resistor, so charging can take place every time only depending on the voltagle levels of the car battery and the NiCd cells. Correct?
5. If I understand #4 correctly, is it possible to add something that would prevent charging when the engine is off (maybe relais?)?
6. My car (Mazda 5) switches CAR_ACC_PWR off during engine start. Some here said that adding a capacitor whould help for holding AVIC_ACC_PWR high for a few seconds during engine start. Can some please explain where exactly that capacitor has to be added and what value this capacitor has to have?
Please excuse me for this detailed questions but I simply want to be sure that I really have understood all this correctly.
Thank You for helping
Regards from Vienna/Austria/Europe
Johannes
Had the same problem with my '08 Hyundai Santa Fe 2.2 crdi AWD and found the following off the shelf solution:
http://www.medienelektronik.de/Artikel/ ... tronik.htm
Should work as plug and play for most cars in Europe with ISO style harness, for the Pioneer you just need one additional Diode in the yellow cable and you are fine. Buffers 5-6 secs, so long enough for cranking.
The implied electronic circuit prevent the dangers usually involved with Caps
Any questions let me know
Jörg
If you are not having voltage drop problems try a time delay relay like this... http://www.drillspot.com/products/49670 ... elay_Relay . Otherwise you will need the setup listed in the AVIC.pdf. You could temporarily wire up your red lead to constant power and see if the radio still reboots when the car is started. From that you'll know which way to go.
Hi!
I ran into the same problems (rebooting when engine is started) with my new F910BT (european model). I am thinking of fixing this with Joe's original schematic (avic.pdf) but I have some additional questions and I kindly ask the specialists here for help.
1. Putting a fuse into the NiCd Battery plus is of course a wise idea. How many amperes should such a fuse be? Someone within this thread said that the AVIC takes up to 10 amps during operation, so should that be a 10 amp fuse or less?
2. Just to be sure I understand the schematic correctly: When the AVIC runs under normal operation does it pull its current from the yellow constant power line? Is this correct? Otherwise if it pulls its current from the read ACC line then this would mean that all the current has to be sourced through Q1 transistor (up to 10 amps?). Do I understand this correct?
3. I assume the diodes should be of Schottky type - correct? Here in Austria I could get MBR1645 schottky diodes (45 Volt, 16 Amps), can I use this type and do they need some heat sink? Do the transistors need a heat sink (mainly Q1)?
4. Someone up in this thread said, that charging the NiCd cells will only take place when the engine runs. If I correctly understand the schematic (avic.pdf) I cannot see this feature. The cells are connected to CAR_CONST_PWR via the 10 Ohm resistor, so charging can take place every time only depending on the voltagle levels of the car battery and the NiCd cells. Correct?
5. If I understand #4 correctly, is it possible to add something that would prevent charging when the engine is off (maybe relais?)?
6. My car (Mazda 5) switches CAR_ACC_PWR off during engine start. Some here said that adding a capacitor whould help for holding AVIC_ACC_PWR high for a few seconds during engine start. Can some please explain where exactly that capacitor has to be added and what value this capacitor has to have?
Please excuse me for this detailed questions but I simply want to be sure that I really have understood all this correctly.
Thank You for helping
Regards from Vienna/Austria/Europe
Johannes
1. 10 Amps is good. A 5A slow blow might be better.
2. All current is pulled from the yellow wire. The red wire is just a signal wire.
3.Yes, no heat sinks needed.
4. They won't charge while the engine is off because the car battery voltage (without the alternator running) will be less than the NiCd voltage.
5. Not needed, they won't be charging then anyway.
6. It would be better to add a timing circuit. Something simple based on a 555 timer IC should be fine.
@maddog hoek
Yes, I have voltage drop problems.
I already tested a solution with relais with delay which in fact did connect the red wire to the constant power (yellow wire) but reboot still did occur because voltage also on the yellow wire (constant power) drops down to a litte bit more than 10 Volts (I think when it will get cold in winter it will get worse).
So I think either a solution with "secondary battery" or with a "big capacitor" are the only two possibilities.
Thank you
Johannes
