Issues after replacing PU-1646 with PU-2184

[Razza]

Hi all,

I replaced my dead PU-1646 cassette head unit (from a 2002 Executive with Sat Nav and multi-CD) with the £50 CD head unit off ebay. It all seems to work beautifully except....

* The Traffic Announcements are sooo loud that I keep thinking my subsequent heart attack will be the cause of the accident in the next Traffic Announcement!
* The difference between the lowest volume setting (mute) and next is too large.
* Automatic Volume settings cannot be toggled

I'm guessing that the 2184 doesn't have the automatic volume control feature (but why the menu option) and/or it's incompatible with the standard amp in the boot. But surely it will be able to store the TA volume? The user guide for the original head unit states that once you adjust the volume during an announcement, it will be used for subsequent TAs. That's definitely not the case and instead some default very loud setting is used. If you have the 2184, how do you change the TA volume? Do I need a hardware mod? What drives the display and hence the menu options?

All advice appreciated! And before you say it, listening to the high quality audio in the car is a life-saver.

Thanks

[mjb]

It sounds like your exec has the JBL amp, which is not really compatible with the normal head units as it expects line-level audio to be sent down the speaker output wires...

I use a JVC AVX33 with mine, which allows (after a little modification to disconnect the VAN bus lines from the power ISO connector) adjustment of the volume to the point it is capable of delivering such low voltages that you don't blow your eardrums...

[Razza]

Thanks.

Shouldn't the TA volume be stored even if the output levels are wrong?

Could I use 1 10K/1K resistor combo to decrease the line voltage levels?
Does anyone the schematic/wiring table for the JBL amp?

I guess I can give up on the Automatic volume control...

[Razza]

I'm looking at getting hold of one (or more) of the line level converters that can eb found on ebay for £8. Will check the wiring in the Haynes first.

If you have a PU-2184, is there a minimum TA volume that is stored? If so, that would explain what I'm experiencing and should not be an issue after I've sorted out the line voltage range.

[FarmerPug]

i changed the cassette radio in my exec for a cd one and also find that volume 1 is a bit louder than before unless loudness is switched off, but even so that doesnt bother me too much in all other respects does the cd radio still work ok with the jbl system i dont notice much difference but whats the jbl unit do is it noise cancelation or amplifaction or just more speakers?

[Razza]

Do you find the volume for traffic announcements is too high?

I also find that sometimes when the ignition is on but radio unit off, I can just about hear white noise on the speakers are switched on, suggesting the amplifier is still on.

Alas, the wiring diagram in my 98-02 Haynes doesn't match my car's wiring. There are two connectors on the amplifier; one connector has 5 twisted pairs (orange&grey, brown&purple x2,red&green, yellow&green) which I guess go to the speakers. Why 5 and not 6 (to include tweeters) or 4 (where tweeters would connect off front speakers)?? Is there a sub-woofer somewhere in the car?

The other connector has 4 pairs of green and brown, a blue, a yellow and a yellow with a touch of green. Do the 4 pairs represent the 4 channel input? If so, is green +ve, brown -ve?

[Doggy]

Try this

[FarmerPug]

razza indeed my radio has those symptoms at the moment, does that mean right now not all the speakers in the jbl system are not being used and the link has plenty of wiring diagrams but i cant understand them, has anyone overcome this problem properly or could i simply put back my old clarion casette player which seemed to work perfeclty in this respect

[Razza]

The link is appreciated, thanks! Unfortunately the wiring diagrams are still a little... different. My twisted pairs to the speakers are on pinouts 1-9, 2-10, 3-11 etc whereas on the diagram it shows 1-2, 3-4, 5-6 etc (speaker connections to 8410 on the diagram).

406ExecutiveHDI, I think the amp is being used. I reckon the JBL amp is still working in the same way as before because it's taking the 4 channel output (L front, R front, L rear, R rear) albeit at higher voltage levels than the amplifier is expecting but still pushing it out to the 5(!?!) twisted pairs. So you needn't worry as all speakers are still in use! I'm also going determined to find out what the fifth pair is used for.

Unfortunately the diagrams don't provide information on polarity so I'll have to test it with a multimeter.

My conclusion is that to resolve the loudness issue, I'll have to spend a total of £16 on a couple of 2-channel line level converters and wire them in before they connect to the amplifier.

Just one question that peeps with this CD unit can help me with... does your CD unit have a minimum TA volume setting that is stored once you switch the power off?

[FarmerPug]

ill check the cd player, but i have never used the ta function on my radio, let me know how well the thing works for you, are the tweeters still working ok on the jbl system is the tweeters up by the windscreen, and what are the 2 things sitting up high on the a pillars

[Razza]

The movement sensors are on the A-pillars. Nothing to do with audio.

[FarmerPug]

the alarm then?

[Razza]

Yep.

[FarmerPug]

have you had any luck yet with the channel line converters?

[Razza]

I've started my experiments and tested which wires are for which speakers but I'm just waiting for a soldering iron to arrive in the post so I can solder some RCA/phono plugs to the socket on the back of the amplifier... The line converters have RCA sockets for connection to the amplifier.

So far so good though. I haven't checked the TA volume but the volume levels are generally lower and the line converters have trimmers should I need to adjust it further.

I'll post a wiring diagram once I'm all done. Oh, and I've assumed that the green is +ve and brown -ve. I couldn't work out the polarity with a multimeter. If the polarity's wrong I'm not sure what noticeable effect that will have on the speakers and sound quality. Will the car blow up???