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3.6 microprocessor / antenna logic.

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Re: 3.6 microprocessor / antenna logic.

Postby M-e-l-l-o-w » Wed Jul 09, 2014 11:31 am

I have not got the wiring diagrams for the early cars. But I may be able to help a little.

The two wires (one red with a green stripe and one green with a red stripe I think??) on the antenna are the up and down positive feeds to the antenna one is for up the other for down.

The negative for the antenna motor is via the antenna earth strap that is just under the wing. Make sure this strap is connected, making a good earth connection and not rotted away!

Trace the same coloured wires that come out the antenna back to the relays. The microprocessor wires at the relay should be smaller than the wires from the antenna, the up one is white with a black stripe and the down one is red with a black stripe. (I think.)

There should be a black wire going to both the up and down relays for the negative that again should be small and the same size as the microprocessor wires.

So by a process of elimination the third thicker wire to the relays should be the constant power feed. I do not know but I would not be at all surprised if this was a brown wire with a red stripe, but I could be wrong.

Make sure there is a constant 12v on this power feed wire.
My guess is that there is not! (But it is just a guess.)

2004 (Facelift 05-MY) 4.2 Jaguar S-Type R in Black.

Morocco Red / Magnolia 4.0 Sovereign Auto Vin.708xxx.Insurance write off on Friday 13th March 2015.

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Re: 3.6 microprocessor / antenna logic.

Postby carlmt » Tue Mar 08, 2016 11:11 pm

Naki - Did you ever get to the bottom of this?

I have a similar problem with the new aerial I have just fitted on the Daimler - new to me anyway but was assured that it worked!

Earth strap in good order and firmly attached to its mounting. Up relay clicks when the radio is switched on (so must be getting the signal) but the mast flatly refuses to budge. No noises from the motor itself (as if it was trying to move the mast).

Time to replace the relays (both up and down) for new ones?

CT 8-)
1990 Daimler 4.0 638778
First registered 01.01.1991

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Re: 3.6 microprocessor / antenna logic.

Postby fiddler2 » Thu Sep 21, 2017 9:43 am

Same prob ariel goes up not down ===take out black relay and it goes down.
Is there some kind of timed delay goin down ? when ok Radio switch off, 5 or so seconds delay it went down.
It did work ok 2 days ago,lots of fun .now it doesn't.
also now back on the road after long storage 3a fuse "breathing heater" blown /what is it?

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Re: 3.6 microprocessor / antenna logic.

Postby naki_k » Thu Sep 21, 2017 8:46 pm

Breather heater is only really something for cold climates. Not generally needed in the UK.
You can replace the breather heater easily enough though. Or just unplug it in the meantime.

All 40 aerials have a delay before the mast restracts.
I didn't ever fix this issue. The car was sold in the end. It could be a duff relay, but I susiected the issue was no 12v signal coming to The relay from the microprocessor. Untested theory though.
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