Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[wpo750]

And there I was thinking it would be a simple case of plug and play...

My XJ has the Infinity system with the amp beneath the rear bench so I purchased the appropriate wiring harness (AUTOLEADS PC9-407). The harness has plugs which mate up with the plugs removed from the factory stereo and the remaining wires I colour coded and butt connected to the plug that fits the rear of the fleabay find, Becker Traffic Pro 7820.  I already have one of these Becker units installed in another car which I managed to hook up relatively easily.

Having completed all the connections I switched on the ignition but there is no response from the Becker. The OEM stereo had a ground wire spade connected to the rear but the Becker has no connection for this. There was a loose black wire coming from the wiring harness, should this be connected to the ground does anyone know?

Also, the head unit appears to have a different antenna connection so this was left unplugged for now. Does the antenna carry power to the head unit per chance?

Oh and the fun doesn't stop there.  The Becker unit benefits from a signal from the speed sensor, is there a convenient location/way from which I can take a feed?

Pardon my ignorance, I've picked an awkward head unit to install and the Infinity setup on the XJ seems to have made it all the more confusing with little relative information I can find on the net. I've tried the 'ICE' specialists so perhaps the Jeep jury can help shed some light.

Much thanks.

[Mike Pavelin]

 Ignore the amp, it won't stop the head unit working. The head unit needs a ground, try grounding the case. The antenna carries no power but is grounded. Antenna adaptor plugs are readily available. The white/orange speed signal wire runs from the speed sensor on the transfer box to the powertrain control module.

[wpo750]

Nice one Mike, I connected the ground cable to the head unit (socket A, pin and it now powers up!  Picked up an antenna adapter from Halfords on the way into work and spent the morning setting everything up.  The only problem I've got now is that I have to enter the code for the HU each time the ignition is switched off and it loses all of it's saved settings.  I'm assuming I've got an issue with the permanent 12v (lack of) which I'll have to investigate later.

So the white/orange wire that comes off the harness already carries a speed signal?  Handy if it does!

Thanks for your help.

[tim_aka_tim]

It's very common for the battery +ve and ignition +ve to get mixed up. Swap them over to fix it. Do it asap,
as you're powering the radio off a low current source that's only meant to be used as a signal for a relay.

[wpo750]

Thanks Tim, that was indeed the problem.  The ignition and battery wire were the other way round and now everything works as it should, almost...

I appear to be suffering some noise interference when the stereo is switched on along with the ignition.  It sounds like a feint whistle/buzz which raises with engine revs.  I tried separating the power cables from the speaker wires and I've further insulated the 12v and ground wires but to no avail. 

Any ideas? 

[Bubba]

soak overnight in a bucket of water sorted

[wpo750]

Only a fool would submerge a car stereo in hot water so should it be tepid or cold?  Also, would adding a few drops of aromatic bath oil help with the poor  reception of Smooth FM? 

[Bubba]

ahh sorry for the lack detail the water should be tepid the bucket should be a 2 gallon farmers bucket before placing the electrical item in the water you must and this is critical stir 3 and quarter table spoons of real not light mayo

[tim_aka_tim]

Ignore him. That trick only works on those new-fangled 8-track players, like Bubba has.

The buzz shouldn't really happen. Have you upgraded the ignition system/alternator or added exotic spark plugs?

Anyway, read this
http://www.fiatforum.com/ice-guides/135760-audio-interference-how-why-what-do.html
It explains what's going on better than I would. Investigate putting a capacitor across the alternator, make
sure it's upto the job - it will be sold for alternators. Look on ebay, it may be sold as a noise filter for
car radios.

If you're still using the amp, another issue could be the line level outputs from the radio. Something
like this http://www.m-99.co.uk/Car_Audio/Noise_Suppressor/noise_suppressor.html might work.

[wpo750]

Hey Tim, no upgrades to mention although it has been converted to run on LPG prior to my ownership.  Never had any issue with the factory head unit though.

That link to the fiat forum looks interesting, I'll have a thorough read of that see if any of it is applicable.

I've not had to use any RCA adapters with the install, nor can I see where they would fit (perhaps directly into the Infinity amp?).  The wiring harness I purchased merely involved plugging into the Jeeps loom and butt connecting to a salvaged ISO plug. 

Worst case scenario I just get used to the whine and just convince myself that the XJ has a supercharger. 

[tim_aka_tim]

The fact that you're not using RCA outputs on the back of the head unit suggests you are using
high level outputs from the speakers into the amp. It's not the preferred method, but it's not
uncommon. In that case, the alternator capacitor should work.

[Bishops Finger]

RCA...that used to be David Bowies record label...

[tim_aka_tim]

RCA...that used to be David Bowies record label...

They actually mean the same thing. Radio Corporation of America.

[Bishops Finger]

Always believe you learn something new every day...cheers Tim

[scoobysnacks]

Ahhhh, good old Fiat forum. Brilliant for all auto electrical problems. Maybe this is because Fiat electrics are crap?

I'm allowed to say that, I own one!