Parking brake bypass

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jus10inbrla

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ive got a ishd01 hdmi to av, and the apple lightning to hdmi adapter. i knew from the past i had to ground the parking brake wire to get past th3 video feature.

fast forward almost a year, i can no longer view videos., thinking my adapters were bad i got new ones. Scratchhhh

wanted new radio anyway .. so while it was en route i plugged everything in to tv. It all works. Get the new radio installed, gues what same issue, the external connection icon blinks off And on …


reading all dif forums, its still unclear on what is needed for these newer boss radios. Do i need to install a single pole rocker switch to “break” the circuit, or maybe it needs it own ground..?
 

Erik the Awful

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i had to ground the parking brake wire to get past th3 video feature.
We don't have a clue what you're talking about. We either need more information, or you're going to have to hope the one or two people who can understand find this post.
 

jus10inbrla

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Ok. Assumed most people knew what it was for.

most double din radios come with either apple carplay, A/V in capable, dvd , media ready etc.

the radio plug has a wire called “parking bbrake”. In normal circumstances since viewing video while driving is illegal, the vehicle must be in “park” and ”parking brake set”.

that wire is hooked to parking brake circuit.

for years, that parking brake wire from radio was able to be just grounded with radio ground, and everything was ok. But in the last couple years, now the radios must sense a “on off on” interruption.

so thats where the rocker switch comes in. To ground and break the circuit, so it can be on off on control. Or installing a relay .

The ISHD01 is a converter with A/V on one side, which goes to the av input (not output) of a radio. And hdmi plug on the other end.

the apple lightning to hdmi is just that. Connect an hdmi between the two devices, and the radio screen mirrors whatever is on iPhone when radio is in av mode.

hope this clears up any confusion
 

1998_K1500_Sub

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thats where the rocker switch comes in. To ground and break the circuit, so it can be on off on control. Or installing a relay .

So can you just use a push-button, momentary-contact, normally-open (or normally-closed, depending on what you really mean by "on-off-on") switch mounted on the dash? Tap the switch once or twice, as needed.

I'm going to assume "on-off-on" means "grounded, floading, grounded".

If you want something fancier and automagic, use an LM556 "dual 555" timer IC, each 555 timer configured as a "one-shot" with slightly different delays and have them drive a relay (or simply the base of NPN transistor, with the emitter wired to grd, and collector wired to that "wire" you mention) to force that "parking bbrake" [sic] line "on-off'on" in the required fashion.


There's probably an even simpler way to do this if someone just thought about it for a minute.
 
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jus10inbrla

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Thats what im probably gona do. More less rite now seein if any else has run across this problem yet.
 

Drunkcanuk

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Well....back in the day when we wanted to go incognito without daytime running lights, we just clicked the e-brake down one notch and they went off. Higley doubt it actually engaged the brakes, so I guess wire as per instructions and give it a click. But in no way am I condoning watching tv while you drive!
 
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