Wiring a head unit for ignition-off use

[Gypsy3000]

Hi.
I've installed a new Pioneer AVH-3500NEX in my '05 jeep liberty. I've been messing with different combinations of yellow/red separate & together wired direct to battery pos (w inline fuse).
Oddly, as soon as I turn-on the ign switch the unit turns off!
I've been doing major work on the jeep for months, but try to top the battery regularly using a trickle charger. If the battery's voltage is on the low side, would that cause such strange symptoms?
It's been 15 years since I've messed with a new stereo install: is there new tech that complicates/prevents direct-wiring a head's power & memory wires together directly to the battery for ignition-off usage?
Many thanks!

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[Slo_Ride 5,000+ posts]

Don't wire both wires together. The constant and switched should be wired correctly.

 

[Gypsy3000]

I appreciate the reply, however my objective is to wire the hu for ignition-off use.
Are you saying that if I follow Pioneer's supplied installation guide and wire the hu's yellow main power-supply directly to the fused battery-feed but the red "signal" wire to a supply that is strictly ignition-on that I should still be able to switch-on the hu with the ignition-off?

How? I've tried various methods, holding different buttons for varying lengths, etc, but nothing will activate the hu with the ignition-off. Conversely, as soon as I key-on the ignition the hu activates normally.
Is there a Trick?

Is there some internal circuitry in these later pioneers that disallow ignition-off use???

Again, could potentially-lowered battery voltage be a factor?

Thanks for your time!

 

[Bobbytwonames 5,000+ posts]

Hit up @Jeffdachef, he is a genius at this type of stuff.

 

[SlugButter]

I would just run a fused power wire from the battery directly, instead of daisy chaining the memory wire. Be sure to cap off your unused ignition wire behind the dash before you finish up.

 

[Bobbytwonames 5,000+ posts]

Ask, @fithwheel, he is the smartest guy on the forum .

 

[SlugButter]

It’s only wiring a power wire. it’s not rocket science. The not so smart ones on the forum can even give this advice.

 

[fithwheel]

It’s only wiring a power wire. it’s not rocket science. The not so smart ones on the forum can even give this advice.

Please don’t turn this into another slugbutter show. I mean you know

 

[SlugButter]

Right. I’m such an arrogant showman

 

[fithwheel]

Right. I’m such an arrogant showman

I know go to bed already. All night with your show again and into the morning? Never mind looks like he finally went to bed about 20 minutes ago lol. Maybe this thread still has a chance.

 

[Jeffdachef 5,000+ posts]

I appreciate the reply, however my objective is to wire the hu for ignition-off use.
Are you saying that if I follow Pioneer's supplied installation guide and wire the hu's yellow main power-supply directly to the fused battery-feed but the red "signal" wire to a supply that is strictly ignition-on that I should still be able to switch-on the hu with the ignition-off?

How? I've tried various methods, holding different buttons for varying lengths, etc, but nothing will activate the hu with the ignition-off. Conversely, as soon as I key-on the ignition the hu activates normally.
Is there a Trick?

Is there some internal circuitry in these later pioneers that disallow ignition-off use???

Again, could potentially-lowered battery voltage be a factor?

Thanks for your time!

why dont you just have an on off toggle switch and wire the accessory and power wire together. Just direct power and ground runs to the battery and a manual on off switch inline the power run.

 

[Gypsy3000]

Thanks for the responses!*

[Btw: I'm a semi-pro mechanic of over 40 years, and owned a commercial recording studio from '80-'02. However, neither of those skillsets are specific to 12vdc latest-tech car audio.]

I was hoping that an external switch could be avoided; I've already installed 5 for aux fans/lights/trlr.brake/airlifts, including an entire aux relay/fuseblock.

I'm having a difficult time swallowing that 12vdc audio companies could be designing units that somehow are electronically prevented from activation independent of a vehicle's ignition circuit. If so, it would complicate the bench-testing of units using a 110vac-12vdc converter (or stand-alone battery).

I wouldn't refer to the red wire as "Memory": it is factory designated to be ignition-switched, which would negate any memory-recall storage functionality at ignition-off. I'm referring to it as a "signal" wire because it transmits current at ign on/off to signal an internal circuit/switch @ hu.

The only function that I can think of that MAY require an ign on/off signal would be auto-restoration of last hu settings, but even that doesn't entirely make sense because the yellow power supply line is constant-voltage and could serve that function. I may well be missing something native to 12vdc current tech (diodes, capacitors, resistors, Oh My!).

I'm going to swap-in a fully-charged battery, double-check my lines, and retest. If the hu still fails to activate normally regardless whether ignition on/off, I'll install a switch on the red "signal" line while keeping the yellow power supply direct-fused.
I'll report-back if/when solved.

Thanks!

*Re the spatting among vets: Life is largely comprised of drama, so why should a stereo forum be an exception: I'm having an affair with both of your sisters (who are actually 2nd cousins), Hardest to take, she let's me walk your dog during your visits to your parole officer.
No worries: in the next episode they will prove your innocence, nabbing the true villain whom dumped gatorade on the matriarch while she presided over the 50th annual debutantes ball. Scandalous!
Meanwhile, your son-in-law is embezzling from the family's carpet-cleaning empire...
[with you, not at you]

 

[Gypsy3000]

SOLVED:
Low Battery Voltage.
I subbed a fresh battery, and;
- HU & Amps perform normally, ignition on OR off.
- HU memory functioning normally.
- HU Requires manual "Off" after ign switched-off. A valid trade-off for ign-off sound!
- If HU on/ign off, when ign switched-on there's a brief delay @HU while it cycles off-then-back-on, but all memory preserved.

TIP: at least w/pioneer flip-screens, the clearest symptom of a depleted vehicle battery is that the screen starts cycling open/close without prompting HU's controls, regardless whether ign on/off.

Thanks again for your input, folks!
Keep on rockin', ridin', groovin' or thumpin'...
Whatever floats your boat, Music Rules!

Cheers