So the story goes, I was looking to upgrade the stereo of my Japanese import HZJ73, a 12 volt system. So I pull the head unit out looking for a 24v to 12v inverter because it’s an all 24 volt system. Well, I couldn’t find one anywhere in the truck and some more investigation leads me to believe the previous owner tapped the 12v headlight power for the stereo and aftermarket rear door speakers and abandoning the dash speakers. I’m looking for options on what to do as I’m not in the mindset (or of the skill set) to pull the harness and undo what has been done, especially considering everything functions as it should.
HZJ73 headlight tap for 12 volts (1 Viewer)
- Thread starter klasseless
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- #2
I should note, it’s a 1992
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- #3
Update for anyone that finds this.
I was wrong. I thought the headlights were 12 volts but they are not and I should have done more research. I'm not really sure where the head unit/speakers are pulling power from now.
I was wrong. I thought the headlights were 12 volts but they are not and I should have done more research. I'm not really sure where the head unit/speakers are pulling power from now.
is there an inverter hiding somewhere? I had a 24V BJ70 that the PO had installed an inverter in for the cigarette lighter and stereo. I don't know if the factory radio's on 24V trucks were 12V or 24V.
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I looked behind the dash but can’t find one. The wiring harness has been cut into in multiple places and there some unusual stuff. Here’s a pic of what I think is an accessory connector.
get a wiring diagram on line or buy one and see how the original radio was wired up.
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- #7
I got back in to look around and I noticed that it appears what’s labeled on the head unit as “battery power” is connected to a wire coming from the A/C amplifier which goes behind the ducting and connects to the head unit. The blue wire spliced in powers a small 10 watt amplifier. Somehow, its pulling power from there but I’m not familiar with the inner workings of the A/C amplifier.
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Do you have a wiring diagram that shows this?
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I'm revisiting this issue and wondering if anyone out there can help me sort this. I'd like to trash the stereo and blown out speakers, rebuild the harness and install and inverter for proper 24v to 12v output but this is my only vehicle so I'm hesitant to cut something out that I need for daily life. Upside is I drive once every 2-3 weeks and don't even really need to so I may be able to fix any potential side effects within that time.
First action item is cutting back all the electrical tape and start tracing some wires since I've got a Aug 1992 wiring diagram.
First action item is cutting back all the electrical tape and start tracing some wires since I've got a Aug 1992 wiring diagram.
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- #11
Update for anyone stumbling on this. The wiring harness is truly ****ed and it's probably not worth the trouble to un-**** it. Instead I'm searching for an entirely new harness.
Get a voltmeter and see if there is 24v or 12v. I too have a HZJ73, everything is 24v EXCEPT the stereo. It’s 12v. Like skullyota said there is one inside the dash. The speakers are powered from the stereo
You can buy a 24 to 12v converter cheap.
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- #14
I have done just that and pulled the head unit out. Not sure how it was originally, but a previous owner cut into the wiring harness completely and the power was coming from a unit behind the glove box, possibly A/C amplifier or something else.
