Question about Malibu Intermatic Inc. ML121RT Low Voltage 121-Watt Power Pack with Timer

2 Answers

Malibu Light Transformer ML121RT troubleshooting

My light string doesn't light up...it did. The clock device continues to turn, I can hear it. Manually turning the lights on and off with the little switch does not turn the lights on and off. There are three terminals on the back and the lights are connnected to A & B. I have a volt meter...how do I see if there is any voltage coming out of the transformer?

Posted by on

Ad

2 Answers

  • Level 1:

    An expert who has achieved level 1.

    Mayor:

    An expert whose answer got voted for 2 times.

  • Contributor
  • 2 Answers

1) Disconnect the plug.
2) Remove the 3 hex screws holding the cover.
3) Make a note of all connections (taking a picture is even better).
4) Connect the black power wire to the red transformer wire.
5) Connect the white power wire to the white transformer wire.
6) Set your voltmeter to 20 or 50 volts AC (not DC and not less than 15 volts).
7) Plug the transformer in the wall.
8) Test the voltage coming from the A & B connectors at the back (polarity is irrelevant).
If you see 12 volts or thereabout, the problem is with the little switch (the one with the black and red wires that is activated by the trippers on the clock dial). I have the exact same problem but I have been unable to locate the part so I am going to try to clean the contact points and see if that works.

Posted on Aug 09, 2009

  • ccss Aug 09, 2009

    Cleaning the switch worked for me so I am back in business.
    This post is to explain how to test/clean the switch:
    1) Review the earlier post to open the box and disconnect/reconnect the wiring safely.
    2) Set your test meter to ohms (resistance, omega sign).
    3) Test your meter by making a contact (short) between the 2 probes: the needle should go all the way to the right. If not, follow the instructions in your test meter manual for using it as an ohmmeter.
    4) Make sure that your transformer is unplugged from the wall.

    5) Connect one probe to the switch red wire and the other one to the switch black wire.
    6) If you don't get any reading, try flicking the switch manually and try again.
    7) If you don't get any reading with the switch turned on or off, the switch is faulty and needs cleaning and/or replacing.
    8) Bend the black plastic tabs back gently and remove the switch by pushing on the little black knob on the outside of the cover plate. This will expose the contact points.
    9) Rotate the little black nob to open the contact points and clean them by blowing air gently, being careful not to damage them. Cover the points with dialectic grease to avoid further problems.
    10) Repeat steps 4-6 to verify that the switch is working. If that fails, replacing the switch is the only solution.

    I will post another solution if I ever figure out what the part number is.

×

Ad
  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    President:

    An expert whose answer got voted for 500 times.

  • Master
  • 1,714 Answers

On your 'AC volts' scale go to terminals A & B when turned on. Should be 12 volts. If there is, check connections to lights. Make sure your trippers are in place on dial.
(Terminal C is for photo cell control)

Posted on Jun 26, 2009

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

One terminal for wire attachment on transformer appears burnt. Fixable or replace?


Something happened to the unit.
Good news is that lights are still ON.
Might be power surge. Or extra wire wrapped around transformer.
Clean up terminal with sandpaper.
If clock motor does not rotate, but lights are ON, then plug power pack into cheap wall timer.
Copy following link and read tips for getting power pack to last longer. One of these reasons may apply to problem.
Plus view warranty, and replacement trippers.
http://waterheatertimer.org/Malibu-power-pack-stopped-working.html

Nov 04, 2012 | Intermatic Malibu 121W Power Pack...

1 Answer

Malibu transformer ml44p doesn't turn off


Check if trippers are worn.
Check if dial rotates and keeps good time.
Plug transformer into cheap wall timer.

Copy following link for trippers, 5-year warranty info, tips to make power pack last longer, and other troubleshoot resources:
http://waterheatertimer.org/Malibu-power-pack-stopped-working.html

Oct 30, 2012 | Intermatic Malibu 121W Power Pack...

1 Answer

I have a malibu set of 8 lights about 80 foot of 12 gauge wire. They come on then after about an hour they shut off then come back on about 20 min later


Do you have photo-eye connected to the transformer?
Disconnect photoeye, or cover photoeye with black tape and see what effect it has.
Plug another light into same outlet and see if it has same problem.
Run temporary extension cord to transformer and see if problem is same.
When the lights are off, does the transformer make humming sound.
Intermatic/malibu timers have 5 year warranty if you have sales receipt.
Copy following link for troubleshoot resources, trippers, operation tips, etc.
http://waterheatertimer.org/Malibu-power-pack-stopped-working.html

Aug 15, 2012 | Malibu Intermatic Inc. ML121RT Low...

1 Answer

Describe your Malibu 121W Power Pack Transformer ML121RT Problem my unit just fryed itself as I had a underwater light hooked up to it. however it took 3 years for this to happen plus I think I had more...


Power pack wattage has to match bulb wattage, or it shortens life of power pack.
I don't know physics and electrical engineering enough to know why this happens.
Also when working on bulbs, manual says to unplug power pack so it doesn't burn up.
If bulb is under water that's fine, but wiring cannot be underwater where it shorts out, or suspect this action might also shorten life of power pack.
With receipt, power pack could still be under warranty.

Open following link for power pack resources, and links:
http://waterheatertimer.org/Malibu-power-pack-stopped-working.html

Aug 23, 2011 | Intermatic Malibu 121W Power Pack...

1 Answer

Had to replace a fixture today. when I replugged the lights the lights turn on manually but the clock on the timer does not advance I have 56 watts of light Is the timer broken?


If clock motor does not rotate, then some people report taking it apart and cleaning gears.
The PB912M10 timer clock motor is not sold separately. Aug 2010.
If power pack transformer still works: buy cheap plug-in timer, set power pack to override, and plug power pack into cheap timer.
With receipt, power pack might still be under warranty.
Open following link for power pack tips and resources:
http://waterheatertimer.org/Malibu-power-pack-stopped-working.html

Nov 29, 2010 | Intermatic Malibu 121W Power Pack...

1 Answer

I have a malibu ML121RT timer that just stopped working. Outlet works, new lightbulbs, didn't nick power cords to outdoor lights. What could be the problem?


The PB912M10 timer clock motor is not sold separately. Aug 2010.
If power pack transformer still works: buy cheap plug-in timer, set power pack to override, and plug power pack into cheap timer.
If transformer no longer works, then it is not repairable.
With receipt, power pack might still be under warranty.
Open following link for power pack tips and resources:
http://waterheatertimer.org/Malibu-power-pack-stopped-working.html

Jun 16, 2009 | Intermatic Malibu 121W Power Pack...

1 Answer

What timer motor fits in Intermatic ML121RT Power Pack ?


The PB912M10 timer clock motor is not sold separately. Aug 2010.
If power pack transformer still works: buy cheap plug-in timer, set power pack to override, and plug power pack into cheap timer.
With receipt, power pack might still be under warranty.
Open following link for power pack tips and resources:
http://waterheatertimer.org/Malibu-power-pack-stopped-working.html

Apr 11, 2009 | Intermatic Malibu 121W Power Pack...

Not finding what you are looking for?
Malibu Intermatic Inc. ML121RT  Low Voltage 121-Watt Power Pack with Timer Logo

5,331 people viewed this question

Ask a Question

Usually answered in minutes!

Top Malibu Hardware & Accessories Experts

Gene Haynes

Level 3 Expert

5089 Answers

Scott Jelt
Scott Jelt

Level 2 Expert

44 Answers

jdthefixer

Level 3 Expert

744 Answers

Are you a Malibu Hardware and Accessory Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...