Power Antenna

[Betterthanux5]

Well i've had my '94 lexus es 300 for about a year now and it is my first car. i've been happy with it for the most part (We have had to fix a lottttta stuff though) but now i am trying to fix the little annoying things. the power antenna was broken when i bought it and i bought a replacement mast and when i was removing the old parts i found they must have take the toothed-cable out when the top of the mast was removed. i tried to just put it in there and see if the motor would turn on and feed the new one in there but the motor isn't even turning on. we think it could be one of three problems:

1. we didn't plug the antenna wire into the back of my aftermarket sterio head unit when we replaced it.

2. the motor is not getting power from the car.

3. the motor is just bad

my question is really related to the second point. we want to figure out which wire on the wiring harness is the grounding wire, or the power wire and hook it up to an amp meter and see if it is getting any power but we are not exactly sure which wire that is. if anyone could help it would be greatly appreciated

[gbhrps]

These motors operate on two wires. Hooked up in one direction, the mast goes up, reverse the two wires and the motor runs in the opposite direction, and the mast goes down.

A test light hooked to the main connector from the timing module (usually on the side of the antenna motor) to the antenna motor when the radio is first turned on, should light up. After say 6 seconds or so it should go out. This gives the motor enough time to raise the mast, and then the clutch mechanism, inside the gear assembly, starts to slip until the timer times out.

The reverse situation takes place when the radio is turned off.

Check to see if you have power to the connector to the timer module when the radio is first turned on. If not, there is your problem. Either you have a break in a wire someplace, or the radio isn't sending any juice to the antenna circuit when its first turned on.

If you do, then see if you have power from the timer module when the radio is first turned on. If not, then the timer is bad. If you do have power from the module when the radio is first turned on and the motor doesn't move, then the motor is bad.

That said, these entire assemblies are easy to remove from the car and take apart and fix. In some cases, the gear box is riveted (grind the rivet heads off or drill them out, and replace with small nuts and bolts when reassembling), in others its screwed together. Good Luck!