Gen 3 Suzuki Jimny 1.3 (M13A) – Cranks slowly, no spark

Thanks for all the suggestions – especially the one about cranking speed and coil testing, which turned out to be very helpful.
I wanted to give an update on what I’ve tested this weekend and check if my conclusion makes sense.

Additional checks performed:
• Checked engine oil level – it was slightly low but still above minimum. Topped up to correct level.
• Removed all spark plugs and turned the engine by hand using a ratchet on the crank pulley bolt. The engine turns freely; resistance varies through the rotation (as expected with valve train / oil pump), but no signs of seizure or abnormal stiffness.

Ignition system tests:
• With the coils already removed, I attempted resistance measurements according to the service manual. This did not give any meaningful results (likely due to internal electronics in the COP units).
• Following the “swap coil” advice, I then performed a proper spark test using a spark plug grounded solidly to the engine with a jumper cable.

Results:
• The coil normally fitted to cylinders 2–3 produces strong, regular sparks during cranking.
• The coil normally fitted to cylinders 1–4 produces no spark.
• Swapping the known-good coil into the other connector still gives regular sparks, which rules out wiring, ECU channel, and grounding issues.

Based on this, it appears that one ignition coil is faulty, and since this engine uses wasted spark (1–4 and 2–3), the engine will not start with one coil completely dead.

Before ordering replacement parts, I’d just like to sanity-check this conclusion with the forum:
Is it reasonable that a single failed coil on this system would fully prevent the engine from starting, even though RPM is seen in OBD and fuel pump runs?

Thanks again for pointing me in the right direction – the coil swap test really helped narrow this down.