G-Series, Drive, and Drive2 diagnostic guides. Gas and electric models covered, including the Drive2 AC motor system and G-series clutch diagnostics.
Yamaha's golf cart lineup spans several decades and both gas and electric platforms. Knowing which model and year you have determines almost everything about how you diagnose it.
The G-series ran for 27 years with multiple sub-models. Key breakdown: G1 (1979–1989) is 2-stroke gas only. G2–G9 span 2-stroke and 4-stroke gas plus early electric variants. G14 onward introduced modern 4-stroke engines and more refined electric systems. G-series electric models run 36V (6×6V batteries) and use a series DC motor with a mechanical speed controller. They're simple, durable, and easy to repair.
The Yamaha Drive (code JNAG, 2007–2016) replaced the G-series. Electric Drive models run 48V with a DC motor and solid-state controller. The Drive2 (JNAG-L, 2017+) uses an AC induction motor — a significant platform change. The Drive2 AC system is more efficient and quieter but has different diagnostic requirements than the DC systems on older models. AC motor failures are less common but require different testing.
Always identify gas vs electric first. The symptoms overlap (won't move, slow, stalls) but the diagnostic paths are completely different. Gas carts have a carburetor, fuel system, ignition, and centrifugal clutch. Electric carts have a battery pack, controller, motor, and solenoid. This guide covers both where relevant.