Aerial switch

[Fin]

I know that this has been covered left right and centre, again and again... But my aerial seems  different to most (typical of my luck   s:? :? s:?  )
My aerial goes up, as soon as I insert the key-tip in the ignition (before I switch anything on) and doesn't go down until I remove the key. No matter whether the stereo is switched on or not?!?!
I have been down the back of the stereo, when I had it out to fit my iPod adaptor. I have pulled off the scuffplate, and disconnected just about everything I can find. All to no avail   s:twisted: :twisted: s:twisted:   Spent a good few hours on it, but I can't find where the feed is coming from. I don't want to start snipping wires randomly behind the dash-board, just in case.
Has anyone else come across one like this? If so, how did you get around it?
Help please!

[StuC]

Can you trace the wires back from the aerial?

[Fin]

I think that's going to be my only option.
I found where they run under the scuff plate, coaxial with 2 wires attached. When I disconnected them, the damn thing still went up!!!
I think I'm going to have to go right back to the aerial motor and creak into the feed there  s:( s:(  I was just hoping someone might have seen this before, and have an idea where the joint is made behind the dashboard.

[StuC]

There is a joint under the rear bins. It might be worth looking there too.

Have a read here

[Fin]

Thanks for that. I assumed I would be taking out the inner arch and trying from there...
I'll have a read up on getting the rear bins out, see which is easier  s:) s:)

[Fin]

Okay, I've had the rear bins out, and it was a bit of a good news/bad news scenario...
I eventually got around to checking the oil for the first time since I bought my little baby, she hasn't used a drop in over 1500 miles   s:bounce: :bounce: s:bounce:  
My passenger bin door is damaged at the bottom, the hinge is a bit ripped (still got over 3/4 of the hinge, so it should be ok especially as I don't really use them for much)   s:( s:(  
I found a couple of loose bits in there, and none of the screws were more than hand-tight, should cure the occassional rattle I was getting from back there    s:o s:o  
I unplugged every connector that even went near that side of the car, and the damned aerial still goes up as soon as I put the key in the ignition     s:roll: :roll: s:roll:  
It looks like I'm going to have to pop the inner wheel arch, and re-wire from as near the aerial as I can get. I just can't work out where the power supply is coming from any further forwards   s:twisted: :twisted: s:twisted:  
Another weird thing though.... If I put the key in the ignition, and do nothing for a minute or two, the aerial goes up and then gets bored and goes down by itself   s:?: :?: s:?:   I just wish I could work out what it's been wired to    s:roll: :roll: s:roll:

[StuC]

That is a strange one indeed.
Does look like you need to be heading for the wheel arch now though.

I like how you are picking out small wins along the way though.  s:-D :-D s:-D

[Fin]

My real win is the oil level, it hasn't moved at all   s:D s:D   With a car over 10 years old, and over 90k on the clock, it's still a beautiful tight drive.
I spend my working life driving 40 tonne trucks, and I had a horrible little Peugeot 206 diesel for years, because of the miles I cover getting to and from work. I'm just happy I finally picked an MR2, after wanting one for a very long time, and it looks like I got a good one   s:lol: :lol: s:lol:   (And, yes, my fuel costs have almost doubled, but who cares???).
I'll lok at getting into the wheel arch next week. I only get oone night off this week, and I've used most of the day already   s:? :? s:?

[fosters4444]

my aerial goes up when I turn ignition on and down when turned off think mine has been changed when a different cd player was fitted   s:? :? s:?

[Fin]

That's the bugger :/ It's the original head unit, so I don't understand why anyone would have messed around with the wiring...

[trevsmr2]

That's the bugger :/ It's the original head unit, so I don't understand why anyone would have messed around with the wiring...

The power to the standard aerial is this one at the bottom of the pic ,which then goes through into the wheel arch ,so removing the arch liner will still not get you to the power source

[spit]

Random splutters ahead.......

Very odd. I'd guess that your aerial has been tied into the "key-in" circuitry which is linked to the immobiliser circuit and also fires off things like the "door open" and "lights on" buzzers.

It seems to do this by making an earth connection rather than switching in a +12v feed, which may (or may not!) explain why unplugging stuff isn't working for you! Certainly looks like your issue is in relation to the making/breaking of an earth rather than a phantom 12v feed (although one without the other is kinda moot but hopefully you see what I'm getting at).

The doings part of the circuit is a yellow wire with red stripe which closes to earth when the key is inserted. The earth point in question is on the front inner bulkhead, slightly off-centre and behind the head unit (black'n'white wire).

I've found the yellow/red feed wire in two places, at both the front and rear of the cabin. At the front it runs from the body ECU plug B5 pin 19 and then goes off to the keyswitch and on to the earthing point via the black/white wire. It also T's off to provide the earth for that annoying beeper on the dashboard panel!

In relation to the immobiliser circuitry, you'll find it at the main ECU behind the passenger rear bin. Plug E3 pin 17. (E3 is the larger of the two inboard plugs).

I don't have a UK immobiliser, but perhaps someone reading this will be able to confirm how long before it resets if you do nothing after you've put the key in? Perhaps that fits with your aerial deciding to call it a day if you ignore it..... and maybe we can isolate the wire that switches back to "dead" when this happens 'cos that'd be a candidate for scrutiny too.

Anyhoo, I'd be inclined to do what you're planning and re-wire it back to where it should be. However, have a look out for any hack into the feed & earthing processes of the car's beeper warning and immobiliser systems so you can tidy it up if necessary.

This is all best guess, but perhaps it'll help you to home in on whats occurring?  

Don't forget to give a wide berth to anything with a yellow plug on the end. Thats airbag stuff that is!  s:shock: :shock: s:shock:

[Fin]

Trevsmr2, that's one of the boxes I found and unplugged. To no avail   s:( s:(   I have a feeling that my wiring has been messed about with, good and proper!!
Spit, a couple of good pointers there, which sound like they may be easier than digging out the inner arch... Sounds like a project for next week, when I have a couple of days off  s:) s:)  You never know, there may be a couple of wires there that I didn't cut last time because they looked like earths, so I left them alone.
If I read right, you are still talking about the wiring behind the Head Unit? and maybe a couple of earths which hide behind the plastic bit to the right of the pedals in front of the scuff plate, sort of the inside of the wheel arch? Hadn't previously thought about killing the circuit through the earth. Used to be an electrician, so I guess it just went against my nature!!

[spit]

Without seeing what you're looking at its difficult to point you anywhere specific, but from your description I'd be looking for a circuit that's going 'live' and then dying in relation to the key-in action (and possibly some sort of to-be-confirmed immobiliser action. Anybody able to confirm that there's a delayed immob reactivation after no activity post-key in??).

If the aerial behavour tallies with the keyswitch and/or immob circuitry, its more likely that its going on behind the stereo than behind the rear bins..... but you never know. Stick to the midline of the car for starters - the scuff plate on the sill could be a red herring as those earths aren't related to the keyswitch and immob earth points. Be careful what you're cutting though...... the info is to help you home in on stuff - I'm in no position to suggest that you start cutting out earths wink:

Earth-to-make circuits may seem odd at first but its quite common on cars - a number of aftermarket warning systems sit idle with a positive feed attached and only spring into life when earth is made. Worth bearing in mind.

[fosters4444]

That's the bugger :/ It's the original head unit, so I don't understand why anyone would have messed around with the wiring...

The power to the standard aerial is this one at the bottom of the pic ,which then goes through into the wheel arch ,so removing the arch liner will still not get you to the power source

this box is missing on my car is it for the aerial thanks  s:? :? s:?

[trevsmr2]

That's the bugger :/ It's the original head unit, so I don't understand why anyone would have messed around with the wiring...

The power to the standard aerial is this one at the bottom of the pic ,which then goes through into the wheel arch ,so removing the arch liner will still not get you to the power source

this box is missing on my car is it for the aerial thanks  s:? :? s:?

yes its the aerial relay

[fosters4444]

The power to the standard aerial is this one at the bottom of the pic ,which then goes through into the wheel arch ,so removing the arch liner will still not get you to the power source

this box is missing on my car is it for the aerial thanks  s:? :? s:?

yes its the aerial relay

thanks very mutch   s:D s:D

[nathanMR2]

Have you checked that your passenger window disable button actually disables the window function? If it doesnt it could have been used to tap into the circuit for the aerial

[fosters4444]

Have you checked that your passenger window disable button actually disables the window function? If it doesnt it could have been used to tap into the circuit for the aerial

the plug of the aerial wire has been chopped of and joined to two of the wires that go to the relay it must be a ignition live will have to get a box and putt wires back to standard hate when people bodge things up   s:evil: :evil: s:evil:  thanks for info and help

[trevsmr2]

Have you checked that your passenger window disable button actually disables the window function? If it doesnt it could have been used to tap into the circuit for the aerial

the plug of the aerial wire has been chopped of and joined to two of the wires that go to the relay it must be a ignition live will have to get a box and putt wires back to standard hate when people bodge things up   s:evil: :evil: s:evil:  thanks for info and help

ill see if ive got the one from the car i broke

[fosters4444]

Have you checked that your passenger window disable button actually disables the window function? If it doesnt it could have been used to tap into the circuit for the aerial

the plug of the aerial wire has been chopped of and joined to two of the wires that go to the relay it must be a ignition live will have to get a box and putt wires back to standard hate when people bodge things up   s:evil: :evil: s:evil:  thanks for info and help

ill see if ive got the one from the car i broke

nice one let me no price if you do thanks

[Fin]

Well, I finally had time to take my inner wing off   s:) s:)   Somebody had done a real butcher's job on the wiring and it took a while to get things right. But at last my aerial only goes up when I want it to  s:D s:D  ). Also finished the wiring for my iPod, at the same time   s:bounce: :bounce: s:bounce:  
However.... I can't remember how the spacers etc went on the mast.
Is there a picture anywhere of what order the plugs/spacer/nuts should go on? At the moment, I have got it wrong, because the damn thing is sitting loose, and won't clamp down onto the wing properly   s:cry: :cry: s:cry: