Mr2 Mk2 - Radio Issues - Help!

[pixel1980]

My MR2 MK2:

Date of first registration 14 01 1994

Its a UK car, opposed to a Jap import.

The car is in great original shape, and had an original Toyota radio fitted that worked fine.

I decided to upgrade, to a Sony CDXGT424U.EUR as it has a CD Player and USB playback.

To cut a long story short, I've fitted the radio, and there's whinning white noise coming from the Speakers, and I'm not happy about it.

The loomed I used to connect the radio to the car is:

Celsus AIS2257 (described as: Toyota MR2/Supra 94 on - RCA)

http://www.celsusice.co.uk (search AIS2257 for an image)

The radio switches on fine. I can play radio, CD, Mp3, and there's an awful whinning noise.

I've tried:

Disconnecting front Speakers

Disconnecting rear Speakers

Unplugging arial.

..and wasting money on a small device (that did nothing) desgined to filter out all noise from alternators etc.

I've now discovered at:

http://www.justkenwood.co.uk/install/show_model.asp?id=270)

there's 2 types of systems: without active (March 1985 onwards) and active (March 1985 to January 1994)

Both dates cover my car.

Do do I know if my MR2 is fitted with active or without active ?

Thanks to anyone who read's this, and has some anwsers :D

[AceAceBaby]

I fitted a Sony head unit the other weekend to mine. If you have Speakers behind the seats, apparently that is the clue that you have the active system.

http://www.dynamicsounds.co.uk/toyota-supr...411-p-3079.html

is a picture of the lead I used, PC9-411. The RCAs plugged into the pre-outs of the head unit (I bought a HU with front and rear pre-outs because of the active system). It worked ok with no whining or hissing etc. I didn't use the ISO speaker plug at all- if you're wiring RCAs into that, then you'll be amplifying and amplified signal which might be why it sounds wrong?

[pixel1980]

I fitted a Sony head unit the other weekend to mine. If you have speakers behind the seats, apparently that is the clue that you have the active system.

http://www.dynamicsounds.co.uk/toyota-supr...411-p-3079.html

is a picture of the lead I used, PC9-411. The RCAs plugged into the pre-outs of the head unit (I bought a HU with front and rear pre-outs because of the active system). It worked ok with no whining or hissing etc. I didn't use the ISO speaker plug at all- if you're wiring RCAs into that, then you'll be amplifying and amplified signal which might be why it sounds wrong?

So I have an active system. I have the AIS2257 Toyota active system ISO Lead, so thats good.

The Sony radio has 2x RCA outs (red/white). The MR2 has 4x RCA connectors (2x red/white). I'm using 2x Y lead/splitter, so both front and read Speakers are connected. The instructions that are supplied with the loom recomend this.

-

I found a link here to someone else with the same problem, and he posted a link to:

http://www.mr2.me.uk/Mk2/ICE1/Mk2_Active_Wiring.pdf

He solved the problem by switching leads 10 and 12

[AceAceBaby]

That sounds ok I think, it means the left and right is just getting branched off to front and rear. Do you have the earth lead fixed, and the little blue n white lead plugged in and everything?

[pixel1980]

That sounds ok I think, it means the left and right is just getting branched off to front and rear. Do you have the earth lead fixed, and the little blue n white lead plugged in and everything?

The blue and white leads are connected. If I disconnect the blue and white lead, the radio fails to work 100%. I think the problem earth related, although the radio is earthed on the metal bracket thats bolted to the car (just like the original Toyota radio was).

I might try the switch leads (to pins) 10 and 12. Its worth a shot.

[AceAceBaby]

Sorry I can't be more help, mine just worked. If you only connect the front RCAs, without the Y pieces adding the rears, does it sound clearer? I'm wondering if that branching is causing some interference back down the wires?

[pixel1980]

Had a guy look at it today. He thinks its all amp related. I'm probably 1 or 2 wires away from a solution.

I've decided to see a radio fitting co to get it sorted :D

[pixel1980]

Had a converstation today on the phone with a radio company.

Their opinion was: My MR2 has a built in amp, and it needs to be bypassed. Which has made me wonder why they sell a loom (that I own) that will never over come the problem of fitting a new radio?

[pixel1980]

Can someone tell me: Where is the MR2 MK2 amp located? - as this is all that stands between my new car radio and a decent sound :D

[AceAceBaby]

I read that it's behind the panelling under the passenger side rear side window. The amp is the "active sound" system, which is why I used the lead for the active system, and yours is supposed to be the same... Ho hum :(

[pixel1980]

I read that it's behind the panelling under the passenger side rear side window. The amp is the "active sound" system, which is why I used the lead for the active system, and yours is supposed to be the same... Ho hum :(

So what are you saying? - my lead is incorrect?

At the moment, I'm thinking I need to locate the wires to the amp and bypass them. It sounds quite easy in theory ;)

[Karma Supra]

I had the same problem on BOTH our active system MR2s, the cure was re locating one of the earth leads in the ISO connector as the lead was made incorrectly.

Sounds perfect now! Just fitted a nice Alpine digital medai system int eh girlfriends car, with MP3 CD changer, iPod and USB leads and a bluetooth handsfree kit that runs through the stereo :D I put a pust on here for the benefit of the search feature, and I think I said which wires were incorrect.

It will be an earthing problem.

[pixel1980]

I had the same problem on BOTH our active system MR2s, the cure was re locating one of the earth leads in the ISO connector as the lead was made incorrectly.

Sounds perfect now! Just fitted a nice Alpine digital medai system int eh girlfriends car, with MP3 CD changer, iPod and USB leads and a bluetooth handsfree kit that runs through the stereo :D I put a pust on here for the benefit of the search feature, and I think I said which wires were incorrect.

It will be an earthing problem.

So all I need to do is locate the earth leads, and relocate one of them (to where?)

[Karma Supra]

I put a pust on here for the benefit of the search feature, and I think I said which wires were incorrect.