A good share of the "won't start" calls we take are fixed over the phone in two minutes. Before you lose a shift, run this list. It goes from the things that are not broken to the things that are, and it tells you when to stop and pick up the phone.
First sixty seconds: the stuff that is not broken
Every forklift has interlocks that stop it from starting or moving. Check them before anything else:
- Is the operator seated with the seat belt fastened? Seat switches and belt interlocks are the number one "no start."
- Is the direction lever in neutral and the parking brake set (or released, depending on the model)?
- On an electric: is the battery connector fully seated and the emergency disconnect pushed in? On a walkie, is the belly button or deadman released?
- On propane: is the tank valve open, and is the tank actually full? Cylinders run dry mid-shift constantly.
- Is the key switch fully on? Is there a fault code on the display?
Cranks but will not start
If the engine turns over but does not fire, you have fuel, spark, or air. On a propane truck, the usual suspects are the lockoff (the solenoid that opens fuel flow when cranking), the regulator, a plugged fuel filter, or ignition. Frost on the outside of the regulator when the truck is running means it is not getting heat from the coolant — low coolant or a blocked hose — or the regulator is passing too much fuel. On a diesel, glow plugs in the cold, air in the fuel after running out, gelled fuel in a January yard, or a plugged filter.
Does not crank at all
Silence or a click is electrical. Start at the battery: terminals tight and clean, voltage up. Then the interlocks above, the neutral safety switch, the starter relay and starter, and the main fuse or fusible link. A truck that has been sitting for a week with a weak battery is the classic version of this.
Starts and then dies
On propane, a truck that fires and stalls almost always has a fuel delivery problem — regulator, lockoff, filter, an empty or frozen tank, or a vacuum leak. On diesel, air in the fuel or a filter that lets it idle but not load. On electric trucks, a battery that shows charge but collapses under load, or a controller cutting out on a fault.
Electric truck is on but will not move
If the display lights up but the truck refuses to drive or lift, it is nearly always an interlock, a fault code, or a low-battery lockout. Check the seat switch and brake, read the code on the display (write it down — it tells the tech exactly where to look), and check the battery state of charge. A tripped main contactor or a blown controller fuse is next on the list.
Cold-weather starting
Ontario winters cause a specific set of no-starts. Batteries lose capacity in the cold. Engine oil thickens and cranks slowly. Propane vaporizes poorly below freezing if the regulator is not getting coolant heat. Diesel gels without winter fuel or additive. If the truck lives outdoors or in an unheated building, a block heater, a battery blanket, and the right fluids solve most of it.
When to stop and call
Some things are not a checklist item:
- You smell propane. Shut the tank valve and get the truck to ventilation.
- Smoke, a burning smell, or a fuse that blows again as soon as it is replaced.
- A fault code you cannot clear, or one that comes back immediately.
- Anything involving brakes, steering, or a mast that drifts — starting is not the only problem.
- You have done the list and it still will not start. At that point it needs a tech and a meter, not a third try.