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

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Sir: I inherited an Intermatic Malibu ML44P transformer and outside lights when I purchased my present home. They have worked fine until now. The lights used to go on and off -- apparently via an electric eye in the transformer. I see no way of opening the black box to inspect timers or clean the lens on the electric eye. I have never been able to set a timer on this transformer because there is no casual way of opening the transformer to access/inspect what goes on inside. Thanks for any suggestions.

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

A 6ya expert can help you resolve that issue over the phone in a minute or two.
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Posted on Jan 02, 2017

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SOURCE: Malibu landscape transformer

If it is keeping time try moving the stops. If it is not keeping time the motor is probably burned out. These transformers don't have a lot of serviceable parts to them.

Posted on Dec 04, 2008

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SOURCE: How do you set the timer on Malibu 300 watt

Make sure there is power to the plug. Then set the clock and install the on and off pins to control the lights. The on/off switch is for manually turning on the lights. The clock should run as soon as it's plugged in.

Posted on Jul 02, 2009

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SOURCE: Malibu 600 watt transformer timer not working.

The timer motor is probably bad. Unfortunately, Malibu transformers have very few user servicable parts :-( , and the timer motor isn't one of them. One cannot even access the internal connections. If you recently purchased the transformer, return it to the store. If the transformer is less than 5 years old, it's still under warranty. In that case visit the Malibu website for instuctions.

Posted on Nov 02, 2009

Testimonial: "Thanks, very helpful info."

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SOURCE: Lost black pin for ML600TW Malibu low voltage transformer

You can go to the Intermatic web site;
Click on customer service and then the tripper order form
or try this direct link to the form: They're only about 10cents each so buy pleanty.

Posted on Jul 12, 2010

SOURCE: My Malibu 200 Watt Power

There is no fuse and no repair parts

I've been all over the website looking for anything that might help the large number of people with Malibu questions. The website has very little information and no parts and the site offers no help except the following:

1) Malibu gets the customer money, and other people troubleshoot for their customers
2) When buying a power pack, the total bulb wattage on the line has to match the power pack wattage
10 - 20 watt bulbs = 200 Watt power pack
15 -20 watt bulbs = 300 Watt power pack
If your power pack is oversized, it will burn out the bulbs and burn out the power pack

3) A power pack makes a humming noise when it has power >>> check your power source if power pack won't work >>> no other troubleshooting is offered
4) Replace burned out bulbs ASAP or the power pack burns out the other bulbs
5) Unplug power pack when working on bulbs [otherwise, the power pack burns out which is why people write fixya asking why their power pack won't work after replacing all their bulbs]
6) Nowhere on the Malibu site does it offer-or-explain burned out power packs or power packs that don't work, but they show plenty of new products for you to buy.

Posted on Oct 19, 2010

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I don't know if it burned out, but something is not right.
Malibu products come with 1-5 year warranty.
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New Malibu product should work for many years.
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You can buy cheap plug-in timer, set power pack to override and then plug power pack into cheap timer.
Otherwise there are no repair parts for power packs other than on-off trippers.
Power packs come with 5 year limited warranty, so you are within warranty period. Good job saving the date of purchase, you outshine with that detail.

For more information on Intermatic/Malibu power packs showing troubleshoot steps, replacement trippers, useful links, warranties and tips:

Add a comment with your experience so others with same-similar problem can benefit.

Also take advantage of fixya expert assistance live.
For a price, expert works with you while you work on timer or any do-it-yourself project.
Fixya is always less expensive than a service call.

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You can go to the Intermatic web site;
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