Automatic start
Generator Not Starting Automatically
This page is for a standby generator that should start on its own when the mains fails, and does not. A set that will not start at all, even from the manual button, belongs on the generator not starting page. The difference is the automatic sequence.
- Mains-fail sequence
- Manual start is a useful clue
- ATS and controller checked
- Onsite across Gauteng
When the supply drops
Why doesn't my generator start when the power goes off?
Because the automatic path never asked it to, or asked it and the start was blocked. Possible causes include the ATS not sending a start signal, the controller left out of automatic, a battery or charger problem, an emergency stop, a shutdown alarm, a wiring input, a mains-sensing fault, or a fuel and starter fault that only shows once a start is requested.
A useful split is whether the engine will start from the panel in manual. If manual works and automatic does not, the engine is less likely to be the first fault. If manual also fails, the visit includes the battery and the starter path as well as the switch.
The full sequence is what gets tested: mains fail, start request, crank, running, and only then transfer. Proving one of those steps does not prove the next.
The steps that can stop it
Start signal, controller, battery and a failed attempt
ATS start-signal problems
The switch may not have seen the mains fail, or it may have seen it and not passed a start to the generator.
Generator controller problems
Manual mode, an uncleared shutdown, or an input the module does not accept will ignore a genuine mains failure.
Battery and charging problems
A set that sits can have a flat battery or a charger that is not holding it. Automatic start needs that battery when nobody is there to jump it.
Generator starts manually but not automatically
That pattern points at the request and the mode, not at a seized engine.
Generator attempts to start but fails
It cranks, or it fires and drops out, after the request arrives. Fuel and shutdowns then join the test. That is different from a set that never tries.
Testing the complete automatic start sequence
The visit follows mains fail through to a running generator. Transfer of the building is the ATS page if the engine is already up and the lights are still out.
Google reviews of ProService Generator Repairs
Google Review
They updated the proprietary firmware on our Generac commercial diesel controller, completely resolving the intermittent starting issues we had been battling for months.
Google Review
Excellent residential generator maintenance in Bryanston. They are quiet, efficient, and replaced our failing battery charger during load shedding.
Common Questions
Questions about generators that do not auto start
What does not auto starting mean?
The standby set does not start by itself when the mains supply fails.
Is this the same as a generator that will not start at all?
No. A set that also fails in manual is a general no-start. This page is the automatic sequence.
It starts when I press the button. Why does the outage not start it?
Possible causes include no start signal from the ATS, the controller not being in automatic, or an alarm that only blocks that path.
Can a flat battery stop an automatic start?
Yes. A charger fault will flatten the battery between outages, so the set is dead when the mains drops.
There is an emergency stop pressed. Does that block auto start?
Yes. An emergency stop or a latched shutdown will hold the start off until it is cleared for a real reason.
The generator cranks when the power fails but does not fire. Where does that sit?
The start request arrived. Fuel and a crank-no-fire fault are then part of the test, on the cranks-but-will-not-start page if that is the whole symptom.
Should I force the transfer switch?
No. The sequence is tested without bridging live gear or defeating a shutdown.
Still unsure what the fault is? Call or WhatsApp 082 057 4605 for onsite diagnosis.
Service Areas
Onsite visits across Gauteng
Technicians travel to the generator. These are the main Gauteng areas. Suburb pages sit under each region.
What to send before we attend
ProService Generator Repairs confirms an onsite visit from these details. Send what you have. A missing model number does not stop the booking.
- Location
- The suburb or site, so the visit can be booked in the right area.
- Make and model
- The generator brand and model, if they are known.
- kVA
- The size printed on the data plate.
- Fuel type
- Diesel, petrol, LPG, natural gas, or dual-fuel.
- Controller model
- The module name on the panel, when it is visible.
- Fault or alarm
- What the set does, and any text on the screen.
- Photos
- The generator, the data plate, and the controller or alarm. Send these on WhatsApp.
Book a Visit
Say what happens when the mains fails
Tell us if it does nothing, clicks, cranks, or starts only when you use manual.
- Call
- 082 057 4605
- Message us on WhatsApp