Generac Generator Weekly Test Not Working: Why It Fails & How To Troubleshoot

Generac generator weekly test not working? Don’t panic! On most Guardian/home standby units it’s usually a schedule or time setting, a battery or charger issue, or an active controller warning. Start with the quick checks below and you’ll know in minutes whether this is a simple fix or a service call.

Why Your Generac Generator Weekly Test Is Not Working?

The generator might fail to do weekly exercises for the following reasons:

What you see	Most likely cause	Safe check	Next step
It never starts at the scheduled time	Schedule/time/date off OR not in AUTO	Confirm AUTO, then check the exercise day/time and the controller clock (DST/timezone can throw it off)	Fix settings and wait for the next scheduled run
It tries to start, then stops (or fails randomly)	Weak battery OR charger not keeping it topped up	Look for “Inspect Battery” or charger warnings; check battery age (3-4 years is often the tipping point)	Address battery/charger first; if it repeats, book service
Weekly test failed and you see a message/code	Alarm/warning condition stopped the exercise	Take a quick photo of the code/message (it saves a lot of guessing)	Follow code guidance; if it returns after a reset, call a technician
This started right after a power outage	Utility feed / transfer switch affecting charger/controller logic	Note timing and check for charger/AC feed messages on the controller	Re-check once power is stable; if it persists, schedule service

Low Battery Voltage (weekly test not running)

If your Generac generator weekly test is not working, the battery is one of the first things to check on a Guardian/home standby unit. The weekly exercise is basically a “small start-up event” and a weak battery can make the test skip, start and stop, or fail with a warning.

What you’ll usually see: “Inspect Battery”, charger-related warnings, or a weekly test that keeps failing even though the generator seems fine otherwise.

Quick safe checks:

• Check the controller first (photo any message or code).
• Check battery age. If it’s older than 3 – 4 years, replacement is often the simplest fix.

For many air-cooled Guardian standby units, a 12V Group 26R battery is a common replacement — just confirm 26R vs 26 terminal orientation before you buy.

• If you notice swelling, leaking, or heavy corrosion, don’t push it – schedule a service or replace the battery.
• If you have a multimeter: ~12.6 – 13.2V at rest is common; consistent readings below ~12.5V usually point to a weak or discharged battery.

To keep this from happening again, many Generac owners use a small trickle charger. A simple option is the Generac OEM charger cord, which helps keep the battery topped up automatically.

Charger / AC feed issues (common on standby units)

Sometimes the issue isn’t the battery itself, it’s that the built-in charger isn’t getting AC power. If you see Charger Missing AC (Code 2780) or similar, that’s often transfer-switch/utility-feed related and best handled by a technician.

To help you choose the right replacement, here’s the official Generac battery compatibility chart.

Fuel Supply Issues (weekly exercise not working)

All home backup Generac generators run on natural gas or liquid propane (LP) fuel. If the fuel is contaminated or the fuel supply is restricted, the unit may not run the weekly test and not start. 

That said, the generator will display error code 1100 if it’s low on gas. In that case, you must ensure that the gas is turned on. If the unit doesn’t perform the weekly test even though you’ve turned on the gas, you must contact an authorized service dealer.

Engine / Spark Problems (self-test not working)

An overheated or overloaded engine can prevent the generator from running the weekly test. It can be due to problems related to engine components or the spark plug. We’ve given step-by-step instructions on troubleshooting these critical issues in the next segment.

Control Board or Schedule Fault (exercise timer)

The generator’s control board may be damaged, preventing it from running the weekly test. For example, 7.5 AMP is fused to the control module of the Propane 20KW Guardian series Generac generator, and you might notice the LCD screen will not display anything. In that case, the generator will not run the test automatically or manually, and you’ll need to install a new control module.

Sensor Faults (oil pressure, RPM sense)

Malfunctioning or faulty sensors can falsely trigger several conditions, such as high engine temperature or low oil pressure. This, in turn, can prevent the engine from running the weekly test.

Generac Generator Weekly Test Not Working: Quick Fixes

Your Generac generator might not run the weekly test cycle even after pre-programming it and running the test manually. In that case, consider resetting and restarting the generator.

Reset the generator:

Step 1: Open the lid.

Step 2: Turn off the electricity/shut down the power of the unit by switching the circuit breaker switch to OFF.

Step 3: Press the red OFF button on the control panel.

Step 4: Press the Enter key.

Step 5: Wait 30 seconds.

Step 6: Press the blue Manual button on the control panel once. This will let the generator start running the test for 5 minutes.

Step 7: Allow it to run the test, and if it doesn’t, put it into the OFF position by pressing the red button.

Step 8: Wait 30 seconds or more until the system cools down completely. 

Step 9: Press the Auto button on the controller

Now you have reset the generator, and it will make three attempts to start. If it doesn’t start, consider following steps 2 – 9 one more time. 

After resetting the generator, manually perform the weekly test cycle by pressing the Manual key from the control panel. If it doesn’t run the test, diagnose the following seven parameters as explained in the next segment and ensure each is functioning properly.

If your generator still refuses to start or shows a warning indicator, it might be linked to the red light alert on your Generac control panel. That guide explains what each warning means and how to clear it safely.

What To Do If Generac Generator Won’t Start After The Weekly Test?

If your Generac generator fails to start after a weekly test, there are seven diagnostics you can do to troubleshoot. I have explained them in detail below:

Diagnosis 1: Check the fuel level

You must ensure that there is enough fuel in the tank. You can check the fuel level of the Guardian/home standby generators by integrating Generac’s Tank Utility propane monitor with the Mobile Link app. 

The utility monitor will notify you when to refuel the unit. Refuel the unit from the fuel port, which is located on the curbside of the unit, and start the generator again.

Diagnosis 2: Check the battery

The issue might be related to the battery, and in that case, you will see green and yellow LED lights turned on the side of the control board. The LCD screen of the control panel will also read “Inspect Battery.” If it does, then perform the following diagnostics:

• Wear safety gloves, open the side cover, and find out if it’s leaking acid. Disclaimer: If your skin comes in contact with the battery acid, it can cause chemical burns. Clean the battery terminals and the compartment if it’s leaking acid with a rug.

• Ensure that the battery is well-hydrated by taking off the lid and measuring the water level with the help of a hydrometer.
• Also, check the battery voltage. It shouldn’t read less than 12.5 V and more than 13.5 V.
• Finally, look at the date code on the top of the battery cover. Consider changing the battery if it’s older than 3-4 years.

Diagnosis 3: Check the oil level

Before you do anything else: on a Generac Guardian / home standby generator, a low oil level (or an oil-related reminder) can cause the weekly test not working / weekly exercise not working problem. These steps are a safe way to check oil level and add oil without touching household breakers or any transfer-switch wiring.

This is the quickest way to fix a Generac generator weekly test not working issue caused by low oil on a Guardian standby generator:

Step 1: Put the generator in OFF (controller)

Press the red OFF button on the control panel.

Step 2: Let it cool down

Wait 5-10 minutes so the engine is cool and safe to check.

Step 3: Open the lid and locate the dipstick

 On most air-cooled Guardian units, the dipstick is easy to reach once the lid is open.

Step 4: Remove and wipe the dipstick

Pull the dipstick out and wipe it with a clean rag.

Step 5: Reinsert and read the oil level

Insert it back in fully, pull it out again, and read the level. The oil should be between the ADD and FULL marks.

Step 6: Add oil if needed (top-off only)

If the level is near ADD, top off slowly with the correct oil. Many models use 5W-30 synthetic oil, but always confirm what your specific Generac model recommends.

Step 7: Re-check the level

Wait a moment, then repeat the dipstick check to avoid overfilling.

Step 8: Close everything back up

Make sure the oil cap/dipstick is seated properly and close the lid.

Step 9: Return to AUTO

Press AUTO on the controller so the unit can run the next scheduled weekly test.

Step 10: If the weekly test still fails

If you still get a warning/code or the Generac weekly test failed, snap a photo of the message and schedule service (sensor conditions or charger/AC feed issues can also block the weekly exercise).

Safety note: You do not need to flip your home’s main breaker or open electrical panels just to check oil level. Anything involving the transfer switch, utility feed, breakers, or wiring is a technician job.

If you want to know more about oil, here I compared some oils.

Quick note if you meant a portable Generac

This guide focuses on Generac Guardian/home standby weekly exercise tests. If you meant a portable generator (gas tank/carburetor), troubleshooting is different. For standby units, stick to controller codes, schedule settings, battery/charger, and basic maintenance checks. Anything involving wiring, transfer switch, or utility feed should be handled by a qualified technician.

Portable generators may involve spark plug/carburetor maintenance, but on Guardian standby units, those deep engine steps are usually not the first place to start.

Conclusion

Finally, you must agree that it’s pretty easy to program your Generac generator for weekly tests. But one of the most popular complaints is that sometimes the generator might fail to restart after the test. If that’s the case, we have already discussed all the ways to troubleshoot it. If that doesn’t work, it is high time to contact the dealer or take support from a Generac-certified technician.

Frequently Asked Questions (FAQs):