Antenna replacement for SIII

The antenna is easier to thread through the bulkhead without bits attached, Alan - and the mast must be fully retracted to avoid damage.

The driveline is attached to the top section of the mast - pushing and pulling. The knob at the end of the mast is usually screwed on - it’s function is to abut the sections as the mast is retracted.

The antenna ‘well’, containing the mast is usually clamped to car body, but the assembly may also be tightened to the correct angle by the loose end bits shown…

The corresponding loose bits on the old set-up may be reused - and you may have to 'modify the holes…?

xj6 85 Sov Europe (UK/NZ)

I’m sorry about previous graphic. This is correct wiring per Paul’s instructions.

This may prove to be the most challenging part of the process. My hope is that the entire mast can be made to pass from trunk to tail light compartment intact. Disconnecting cable from mast may be the only way. I’d welcome any thoughts…

I don’t believe I can be of any further assistance with the installation of your aftermarket antenna. The only suggestion that I have is try to do the reverse of what you did to remove the OEM antenna and snake it through the rear bulkhead of the trunk and into the cavity behind the right fuel tank. If the aftermarket antenna is close to the same shape and size of the OEM antenna then it might fit. If it is significantly different then maybe not.


That was how it was done with the original set-up, Alan - disconnecting the aerial lead and the brackets to remove. And replacing, as usual, is the reversal of the procedure…:slight_smile:

The aftermarket may of course differ in some detail - you can but try. I had no problems apart from the fiddly treading…

xj6 85 Sov Europe (UK/NNZ)

Fiddly threading is the worrisome part if I have to go that route. I’ll be contacting Retro tomorrow to get some guidance.

The “rigid” length of Retro is about 1 3/8 longer than original…just enough to prevent mast from turning the corner once you’ve fed mast into tail light compartment.

A bit discouraged at this point. I’ll speak with retro tomorrow. Here are afew pics of my efforts.

I wonder if increasing the diameter of the hole that the antenna goes through leading into the tail light cavity would allow the antenna to fit through. Perhaps a small grinding wheel on a dremel tool might do it? It has been a while since I removed and replaced a SIII antenna and I am a little unsure about how large that hole is and what it looks like.


Pending advice from the 'retro - there is nothing to be done with the ‘rigid’ bit, Alan…

Will the ‘rigid’ bit fit inside the wing with the ‘threading’ completed? If so; Paul’s point is valid - enlarging the ‘threading’ holes in the car’s body. Except changing to a different unit…

xj6 85 Sov Europe (UK/NZ)

RE: creating larger openings…The “trunk” end of channel, a small slot has to be made where grommet was to accommodate the antenna cable input fitting, But the enlarging the fender compartment would be major undertaking, not amenable to Dremel cut.

I’ll see what Retro people have to say today…

Haven’t heard back from Retro. If this doesn’t work out, I’m considering returning it and ordering one on EBay. Any thoughts?

The original Jaguar part number for this antenna is DAC4090. If you look at the websites for some of the USA based Jaguar parts suppliers like Moss Motors, SNG Barratt, and Welsh Enterprises and search “DAC4090” you will find that they all carry new ones. If you search eBay for “Jaguar DAC4090” you will also find some used ones that may work or could possibly be used for parts to fix yours. If I were you I would purchase something from a reliable supplier that knows these cars, rather than something that might work from someone that may not know these cars.


[quote=“Alan_Munson, post:71, topic:398466, full:true”]
Haven’t heard back from Retro. If this doesn’t work out, I’m considering returning it and ordering one on EBay. Any thoughts?

Firstly, Alan; the ‘ebay’ shown will not fit your xj - there is not enough room. They are meant for Jaguars with single tanks and more room in the wing. That said; some have indeed sourced a ‘compact’ antenna and motor that is small enough to fit - but I don’t know the details…

The length of the ‘rigid’ bit, the mast well, is dictated by the length of each mast section. In your case, either total mast length is longer or fewer sections than the original.

If possible; you can detach the extension from the mast well - which requires releasing the driveline from the motor before splitting, ad remove the mast and driveline. The fit the mast well in the fender, reconnect the extension, reconnect the driveline and mast. And I don’t know if it possible or practicable…?

You do not mention if your ‘old’ antenna is in working order, except for the broken mast. If OK you may be able to source a mast, and replace it. For obvious reasons; spare masts/drivelines are available for most antenna arrangements…

The ‘best’ option is, as Paul says, to source an OEM, or cloned, replacement.

The specifics of the Jaguar set-up is the extension ‘Bowden’ arrangement - which also requires a longer driveline between motor and mast. If the extension is detachable without damage; there are ways and means of grafting it to ‘any’ antenna set-ups - motors and masts are much of a muchness throughout. But it is a bit laborious…:slight_smile:

xj6 85 Sov Europe (UK/NZ)

Ordered a DAC4090 from Moss Motors. I’ll see if anyone with a 72 -79 XJ wants a new Retro…

1 Like

It may require the ‘old’ external relay, Alan - but no matter…

The ‘retro’ unit will meet the same problems on all ‘series’ Jaguars, of course.

xj6 85 Sov Europe (UK/NZ)

Paul, Frank, etal… I received the DAC4090 yesterday and managed to pass the mast/antenna from trunk to fender bay without too much trouble. .I’ve reinserted the blue/white & blue/red wires into the appropriate slots in the solenoid. Then I tested DC voltages…

  1. Ignition, radio off, battery hooked back up…blue/white = 11.6V
    …blue/red… = 0.06V
  2. radio on…blue/red…11.7V
  3. radio off…blue/red…11.7V, and after ten second dropped to 0.05V

Can I therefore assume that RED from new antenna goes to BLUE/WHITE
GREEN " " " " " BLUE/RED

I guess I’m a bit anxious that when I do make final hook-ups I’ll mess up drive cable or something…?! I will, of course, have proper ground.
It appears motor will fit in original mount.

I was interested in your “Retro Antenna” you posted in the Classifieds! Sent two PM to your listed email with no reply! Have you sold it? If yes, no problem! Just need a reply.


I’m so sorry Richard. My email is You could also call cellphone number

Referring to the wires at the relay, Alan;

  1. blue/white is then the ‘down’ wire
  2. blue/red is the ‘up’ wire
  3. The relay holds ‘up’ power for ten seconds
    • the mast stays up for those ten seconds.
      after turning radio ‘off’. However,
      importantly(!), the relay should then switch
      power to ‘down’ wire (blue/white) - to retract

You do not fully describe fully the wiring on the new antenna - and whether the new antenna is meant for external relay operation. The above describes the correct relay(!) operation.

Your relay blue/white to motor red and relay blue/red to motor green is only correct if motor red is motor ‘down’ - and motor green is its ‘up’ wire.

I assume that the manual for the new motor clarifies what is what…?

As an aside; as no current is flowing through the measured circuits you should read battery voltage and '0’V. If battery voltage is indeed 11,7V; it is too low - though both readings may reflect a meter error.

It has no effect on antenna operation when correctly connected, of course…

xj6 85 Sov Europe (UK/NZ)

No Richard, I have not sold it.