Radio unit rebooting on cranking

@mechanicjon you beat me with answering all questions .

This is valid point, but that is not really for the ignition switch cutting off the power from ACC when key is turned into START position, in general the radio might reboot when cranking from the weak battery (or dirty battery clamps) because of the voltage drop. But I would say if this would happen, then driving with such battery is just asking for a roadside assistance call waiting to happen.

And I did the test. I just proved that ACC is switched off when the key is turned to START position (without even cranking). I did not need to pull the Starter fuse, I have a manual so when I did not press a clutch the starter did not turn. But ACC went off.

 

Not really cutting factory wires. You can tap into 4WD or any other circuit turned on by IG1 and put a diode to this new wire. If you have aftermarket radio you already cut or interfaced factory wires for it. Cut the power wire in intermediate harness and put the second diode. Connect both wires (your pigtail from 4WD and intermediate harness power wire with the radio. Very simple to do, the only PITA is I will have to take the radio out to get access to all wires on the back.

 

I was thinking, what the heck, I can go with my original concept and put a diode just behind the ignition switch so all ACC fuses are powered during cranking. Just connect via big ass diode (something like 25A) IG1 (Black/Yellow) with ACC (Blue/Red). In my 95 ACC is powering only a radio and cigarette lighter fuses.

But then I followed the diagram and I noticed the cigarette lighter fuse is powering also the airbag sensor. It is strange as the airbag sensor is powered by ACC and Ignition. See the diagram below:




The description explains that (7) is powered in key position IGN and START, while (8) is powered when key is in position ON and IGN. Then I got cold feet. What if Airbag Sensor Assembly is not expecting power at (8) while cranking? Will the airbag explode to my face when I start cranking? I don't want to risk it. Never mess with Mother Nature, Mather in Law and Mother F***er Airbags (loose copy from Italian Job movie ).

So I just bought few 10A diodes and will stay with safe "radio only" concept.

 

maybe run a wire from the starter signal to the radio, put a diode on that wire and one on the original radio 12v wire?

 

Working circuit was already presented by @mechanicjon - the difference for me is that the alternative power comes from 4WD fuse which was not used in my truck and I used it to power add-on LED DRL. I was just exploring all possibilities.

 

Is the reboot that bad that you have to wire it this way? I'd understand if it were one of those chinese android double din's.

 

It's only 5-7 seconds which is OK for music to come, but pain in the rear end when when waiting for backup camera to come. Newer radios have backup camera "hardwired" to the display so even the radio is not ready for AV operation, the backup camera image is shown as soon as the power is applied. This one (Planet Audio deck) treats the backup camera as any other input so the radio has to go through the splash screen before it is ready for selecting the backup camera input. Stupid design but other than that it fits my needs 100%.

 

Aren't they all made in China or at in the Asian countries? I have a Pioneer, a decent deck it takes 5-10 seconds to boot up. It has to load the operating system just like a computer.

 

Does your have to finish boot up before it shows the backup camera?

 

No matter how you wire it the voltage may drop enough when cranking and cause the radio to reboot, but give it a try.

I had a similar problem. I have SiriusXM radio and it keeps up to a one hour buffer of several stations that you can rewind as long as the stereo stays powered. If I turn the engine off and restart it cuts power and I lose the buffer. I put some diodes in with a capacitor to keep the voltage up while cranking but it still only works half the time. I need to go back and redesign my circuit!

 

If this is a case, then capacitor is not good enough unless you have some big ass scuba tank size. I would rather use 4S LiFePo4 batteries powering radio on cranking. 1100mAh (A123 brand) would be more than enough. Or you can get fancy and tap the radio to dual battery setup.

 

it is a computer!

 

yes

 

Usually the radio only draws a small current from the switched power (ACC). This just signals the radio that it's allowed to be on. The constant power supply is what provides the bulk of the current. At least this is what I found with several radios. So, the capacitor doesn't need to be too big.

You need to hook a voltmeter to the wires and measure the voltage while cranking to see when your specific radio shuts off. I mean after you set up the preposed circuit.

 

Not really, the android double dins have a longer boot time. Well, the ones reviewed on youtube a while back. I stopped looking at android double dins for the time being but a quick peak on youtube shows they have been improving on boot times and seem to be looking better and better.

 

Oh man, that sucks.

 

I DID IT !!!

Short version: Radio is still rebooting because of voltage drop during cranking.

Long version read here https://www.tacomaworld.com/threads...k-or-rysium-build.457350/page-5#post-15851587

 

I have posted a short video on youtube showing the real boot time of my

$143 Planet Audio P9640B Car Audio Stereo System - 6.2" Double Din, LCD Touchscreen, Bluetooth Audio and Hands-Free Calling, CD Player, DVD, USB, SD, AUX in, AM/FM Radio Receiver

Planet Audio P9640B deck. This is the time from turning the key to start playing audio or in case of the backup camera from turning the key to the moment when backup camera image appears on the screen. This video shows how easy the manufacturer can claim 5 seconds boot time and not lie about it. Every time the radio booted in less than 5 seconds counting from the turning the key to showing the basic screen, but as you see depending on the source selected it takes much longer to actually start playing. Even FM radio takes about 3 seconds to tune up and start playing. This probably explains my urge to made a backup battery for this unit.

https://youtu.be/Zdy6S9gCzgo

 

After reading through the thread till I got to almost the end I wondered what the big deal was.

Now seeing it is because you have to wait for the back up camera via the radio boots up.

Work got me a cheap back up camera a few months ago I think about installing it now and then.

I really hope my 8 Track player keeps on working