JDM400

Hi all, new here & relatively new to Lexus ownership (well, technically, it's a Toyota Celsior but, please don't hold that against me); I say "relatively new to Lexus ownership" as I purchased the car a little over 3 months ago but, I only took delivery 2 weeks ago (long story)...

Anywho, it has a few electrical issues, the first of which should be a relatively simple fix; the car has an aftermarket Kenwood head unit, all wired in correctly but, the rear door speakers don't work; the speakers themselves are fine, as is the head unit (I had it working fine in another car 2 weeks ago) but, when I did a continuity test on the 4 speaker wires from the dash to the doors, there's nothing; my question is why is there no signal?

I've read that, with aftermarket head units, the rear shelf subwoofer & amp no longer work but, what does that have to do with the rear door speakers?

Speaking of the sub, if anyone knows of a way to get the amp working off the Kenwood head unit, I'm all ears...

Yamae

You didn't specify your model/year and I can't give you enough information but at least I can say is that you need a special adapter unit called Beatsonic AOK-03, SLA-21A or SLA-22 to make it possible to drive all speakers if your car was manufactured after October 94. Another method is to make an equivalent of those unit using your own or someone's skills. But this requires you some extra efforts even if you are an electronics engineer.

Search the forum and you will know more. There were many people who have tried to use aftermarket head unit and failed without using the Beatsonic adapter unit.

Moarpower

I have a pioneer touchscreen in my 91 celsior and it's driving the 4 speakers just fine. I literally just made a surround and spliced the wires to the plug for the rear of the head unit.

​​​​​​as for the sub, mines not running either and I don't really miss it.

JDM400

Oops, my bad; I can't give you a build date (it's an import so, when it was complianced for Aus, the factory Jap compliance plates were removed) but, it's a UCF11 & the last 4 digits of the VIN are 0093 so, I'm guessing somewhere around late '91, early '92

I know right? I've done this dozens of times, as well as wiring comp level systems but, for some silly reason, I can't figure this one out...

Here's the weird part, I want to keep the factory sub for "authenticity" but, I'm changing just about everything else about the car (huh); I plan to build 2 12" sub boxes, one on either side of the boot (trunk), the CD stacker & tool kit box are already gone; I also want to remove all unused/unnecessary wiring (copper is heavy) & use a stand alone engine ECU; that's just the tip of the iceberg...

Moarpower

Spending money on the standalone ecu is in my opinion, one of the first serious mods that people should do. It really does make a difference. I really want to simplify my celsiors wiring.

JDM400

I think I may have discovered the reason for this issue; it suddenly dawned on me last night that this car originally had the reclining rear seats & full service arm rest with the A/C controls & CASSETTE PLAYER which runs off the rear door speakers

Disconnecting & removing this unit must have severed the speaker wires so, I guess I'm tearing the looms apart...

Moarpower

Not sure if it is your issue but my rear seat audio is still connectd also.

JDM400

(Well overdue) UPDATE:

Since I've been busy with other projects the past 6 MONTHS, I never had time to look into any of this until a few weeks ago; the good news is ALL SEVEN SPEAKERS ARE NOW WORKING

Having said that, it was no mean feat, I practically had to rewire the entire cabin. The main issue was (WARNING: NOVELLA AHEAD) this isn't one car, it's two; "What does that mean", I hear you all ask; well, I purchased car #1 which had a good drive train, low(ish) milage & a decent cloth interior (I'm not a fan of leather) but gaudy 20" wheels, only 2 air struts in the rear (one of which blew out on the trip home (that's a whole other story)) & a body that had more hits than Elvis; I also secured a deal on car #2 which had everything there except engine, trans & interior (see where I'm going here?)...

I then spent two days transferring the interior & pulled the engine/trans & left the seller to service both & drop into car #2 (he does this for a living); in the process of switching the interior, unbeknownst to me at the time, the two main plugs on the left side of the trans tunnel were wired backwards from each other; ie: the A/C plug from the new dash went to the radio socket of the new car & vice versa but, that was only the first issue...

Since car #2 was the full luxury pack, with reclining rear seats & the split stereo system, & car #1 wasn't, once the original rear seats were removed, certain circuits were severed (including the rear door speakers which work off the rear stereo via an interrupt)...

Long story short, I ended up removing the seats & carpet & traced the necessary wiring while also removing the now redundant 6 stack CD player wiring; it turns out that the rear speaker wires (among a few other redundant wires) ran into the boot (trunk) & back into the cabin, where they then connected to the rear seat harnesses; so, what did I do? I REMOVED THE LOT & left only what was needed; the rear speaker wires now run from the rear doors directly to the head unit as opposed to into the boot (trunk) then back in to the rear seat harnesses them split & run to the dash, a full 6 METRES (20') of just speaker wires...

I know some of you are now cringing in disbelief but, with the help of an internet sourced wiring diagram (which wasn't easy to find) & a LOT of investigating, I managed to remove a LITERAL BUCKET FULL of wiring &, as mentioned earlier, ALL SEVEN SPEAKERS ARE NOW WORKING...

The downside is, ATM, the rear "air purifier" isn't working (which is of little consequence) & the rear windows still don't work but, I'll get to that... & there are about 6 wires which go nowhere

The other upside (apart from the obvious) is everything still works (that I currently know of)...

JDM400

Well, it turns out I have created an issue, although, I don't know how; the rear air suspension relief valve is now not working but, I don't recall removing any wiring from the attached plug (although the plug is empty); looks like I'll be calling in the pro's for this one...