Jaguar XJ6 (X300) Power Antenna Stuck or Dropping
Before buying an aerial motor, look at the mast. A dirty mast snaps the plastic drive tape, and a cheap copy mast makes a working unit grind. An aerial that drops by itself while driving is different: the motor is fine, and the fault is between the radio and the aerial.
How bad is it · Safe to drive
Safe to drive — nothing to do with the car's health
A mast stuck up can be bent by a car wash or garage door — keep that in mind until it's fixed.
Which one applies to yours depends on your symptoms, your model year and what has already been done to it.
Likely causes, most common first
Read the check cost before the odds: a free check that rules a cause out beats a likely guess that costs money.
A dirty, seized mast that has snapped its drive tape
A toothed plastic tape in the unit in the boot pushes and pulls the mast. Dirt and light corrosion make the sections drag, and the tape eventually breaks under the load.
The mast sticks part-way, needs a hand to go down, or stops while the motor still whirrs. It looks dull or rough. The motor can be heard running but the mast doesn't move: the teeth on the tape have worn or broken.
Run it up and wipe it with alcohol or a silicone wipe, upward strokes, then cycle it several times. Avoid oily sprays — they draw dirt into the motor. A dry PTFE silicone on a cloth after cleaning is better than any oil.
If the tape has broken: take the unit out of the boot, open it, clean the gears and drain, grease them with silicone grease and fit a new mast. The mast tube can corrode tight, so take care removing it. Only the mast and its tape need replacing, not the whole unit: with the radio off take the top nut off, switch on to drive the old one out, and feed the new tape in. Use a plastic-safe white grease on the gears, not the old black grease.
A cheap replacement mast that doesn't fit
Copy masts vary. A shoulder a fraction too wide at the bottom stops the top section and makes the motor grind; others are too loose and wobble, or rust at the top within months.
The trouble began with a new, cheap mast: the first section won't move, it grinds, or the mast wobbles when extended though the nut is tight.
Compare the new mast's bottom end with the old one. A genuine mast drops in easily. A genuine mast from the original maker is worth the extra; copies are often rattlier.
Fit a genuine mast. To keep a copy, take a few thousandths of an inch off the bottom shoulder — no more, or it pulls through — and smear the tape with petroleum jelly. If a new mast binds part-way down, back off the top nut — overtightened, it pinches the mast.
A piece of the old tape left inside the reel
When the old tape snaps, the broken end stays wound in the reel housing in the boot and blocks the new tape, so a fresh mast behaves worse than the old one.
A new mast that won't extend or retract fully, leaving several inches showing, or grinds at the top.
Lay the old mast and tape beside the new one: if the old tape is shorter, the rest is still in the reel.
Take the unit out of the boot, open the reel housing and pull out the fragment, then refit the new mast. It saves buying a complete unit.
Ticking through the radio with engine speed — the ignition
Each plug on the six-cylinder has its own coil. A coil not fully seated, or corrosion on its spring contact, sparks where it shouldn't and the radio picks it up.
A tick in the speakers that rises with revs, often after plug, coil or head work. A buzz worse at idle and quieter as the revs rise can be a cracked coil, often appearing after the engine bay has been washed.
Pull each coil and look at the contact spring and plate for corrosion. Play a CD or tape: if the noise is there too, it isn't the aerial or the tuner. Check the engine-to-body earth and the radio's own earth as well.
Clean the contacts and push every coil fully home. Replace cracked coils; on this engine look at them at every plug change.
No fault: the pause before it goes down
The aerial is driven by the radio. Switching the radio off retracts it only after a delay of several seconds, and it stays up for a CD or tape on cars that listen for traffic news.
The mast seems to stay up when the radio is switched off before a car wash.
Switch the radio off and wait a few seconds before deciding it's stuck.
Nothing to repair.
The aerial drops by itself — the signal from the radio
The aerial has a permanent supply and only takes an up or down signal from the radio. If it moves at all, the motor works; dropping on its own means the signal is lost at a loose plug or inside the radio, where dry solder joints are common.
The mast goes down while driving and stays down until the next start; sometimes the CD changer drops out at the same moment.
Wiggle the wires at the aerial end behind the boot lining, then the plugs behind the radio. If both are sound, suspect the radio's joints near the aerial output.
Worth trying: reflow the solder joints round the aerial signal on the radio board.
Motor runs on at the top, or stops short
The drive stops when it meets resistance at the end of travel. A worn rubber ring in the chrome fitting on the wing lets the top section over-run; a broken plastic gear inside stops it short.
A gear-jumping noise once the mast is fully up, or a mast that never reaches full height. A loud grinding that stops after a while is the gears in the motor unit.
Look at the rubber ring in the chrome fitting. If the mast stops short, open the unit and look at the main gear teeth.
Worth trying: a new rubber ring for over-run; for stripped gear teeth, a used aerial.
AM full of static, FM fine — the aerial lead
A poor connection in the aerial lead hurts AM far more than FM.
FM clear, AM unusable even near a strong station.
Check the lead where it joins in the boot, then at the back of the radio.
Worth trying: remake the joint in the boot and work the plug at the radio end.
The order to check them in
The point of the order is money: each step either rules a cause out or makes the next one worth doing. Green is free, amber costs a little, red is the one to arrive at last.
Clean the mast, several cycles
Alcohol or a silicone wipe, upward strokes, radio on and off a few times. Not an oily spray.
freeDoes it move at all?
If it moves, the motor is alive. Dropping by itself points to the plugs and the radio; grinding points to the mast.
freeSwap the mast from the top
Nut off, radio on to drive the old mast out; new tape in, teeth facing the side of the car, radio off to draw it in. Compare the old tape's length with the new.
a genuine mastIf the tape is short or broken, open the unit
Out of the boot, open the reel housing, remove the broken piece, clean and grease the gears, clear the drain.
free, an hourTicking with revs: go to the coils
Reseat and clean every coil contact before touching the radio.
freeWhat it usually isn't
Don't spend money here first:
On jagaux.com
- XJ6 (X300) fuse boxesThe aerial has its own permanent supply — if it is completely dead and silent, start here.
- XJ6 (X300) radio pinout and wire coloursWhich radio pin sends the aerial up and down.
- Jaguar radio code generatorFree. For the X300 factory radio, if it asks for its code after the radio has been out.
- Jaguar XJ6 (X300) Trunk Won't Open, Boot ReleaseIf pulling the aerial fuse has left the boot shut and dead.
- Jaguar VIN decoderConfirm your exact model year, engine and factory options before ordering parts — free.
Ratings, fuse numbers and torque figures vary by model year and market. Read the legend on your own car before pulling anything, and use the figures in the manual for your car, not the ones in a video.
Check your VIN: exactly which car you have and which bulletins apply to it.