Anyone replace the mast on a Commodore Electric Aerial?

[ArnieVXR]

My one is broken. The motor runs when the radio is switched on and off.

There's plenty of videos on Youtube showing you how to replace the mast. Trouble is, they're all for aerials that 'sit' on the wing, rather than poke through it.

[L2VXR]

taken from holden manual.

MAST REPLACEMENT
The following procedure is for replacing a damaged or faulty antenna mast and drive cable assembly.
1. Remove power antenna assembly as previously described in this Section.
2. Remove chrome plated nut from top end of mast tube.
3. Extend damaged antenna mast as far as possible by attaching battery negative via a jumper lead to antenna
mounting bracket and battery positive to both the antenna red and white wire terminals.
At end of mast travel, pull out mast and drive cable from antenna housing.
NOTE:
If mast is too badly damaged to extend, grip tip of mast with a pair of pliers and pull mast and drive cable assembly
up and out from antenna housing.
4. If necessary, remove contact spring (metal sleeve) from old mast and drive cable and install onto replacement
mast and drive cable.
5. Feed end of drive cable down mast tube of antenna housing with serrated side of drive cable facing toward the
centre of the housing. Continue to feed drive cable down until it engages with the drive mechanism.
NOTE:
It may be necessary to twist the drive cable clockwise and anti-clockwise slightly to enable end of cable to feed
through opening at base of mast tube before it engages the drive mechanism.
6. With the aid of an assistant to hold the antenna and mast assembly, connect antenna mounting bracket via a
jumper lead to battery negative.
7. Momentarily connect battery positive to the antenna red wire and drive mechanism should start to retract drive
cable into antenna housing.
8. With the drive cable engaged to drive mechanism, reconnect battery positive to antenna red wire and allow
drive mechanism to wind in drive cable and mast into mast tube and housing.
9. At this stage the mast might be fully retracted into the mast tube and housing. Reconnect both the red and
white wires to battery positive and allow the mast to extend fully until the motor stops.
Disconnect white wire from battery positive and allow mast to fully retract.
10. Reinstall chrome plated nut to top end of mast tube and tighten securely.
11. Reinstall power antenna assembly as previously described in this Section. Check antenna mast operation.
CHECKING ANTENNA MOTOR OPERATION
NOTE:
The following ‘Checking Antenna Motor Operation’ tests are made at the main wiring harness to antenna motor
connector located at the right hand cowl panel, above the engine management powertrain control module.
The voltages shown are measured to a good earth point on the vehicle body.
VOLTAGE ON ANTENNA HARNESS WIRES
Red White Action
12V 12V Antenna extends
12V 0V Antenna retracts
0V 12V Antenna does not move
0V 0V Antenna does not move
If the antenna motor does not correctly respond to the inputs as specified, ensure that a good earth connection is
being made through the mounting bracket by measuring the resistance from the bracket to a good earth point. If
more than 1W replace power antenna assembly. Check that the forked earth connector is securely attached to the
antenna mounting.
NOTE:
If there is significant noise on the AM band (with radio tuned to weak station outdoors), then check antenna earth
quality. The antenna earth terminal has a large effect on the screen.

[ArnieVXR]

Excellent - thanks