RAV4 Hybrid Engine Start Problem

Sounds like a pain! I had a similar issue with my old Renault Megane, though it was petrol. Engine wouldn't crank at all. Turned out to be dodgy battery cable connections, even though they looked alright at first glance. The corrosion was hidden. Have you tried cleaning the terminals properly, like taking them off and scrubbing them, and the clamps, down with a wire brush?

Hmm, I just gave them a quick once-over. Didn't actually disconnect and scrub. Is that really likely to stop it from starting completely?

Yeah, electricity is like water, it finds the easiest path. If the connection is bad, the current might not be enough to kick the starter motor, like trying to fill a swimming pool with a garden hose. I'd really recommend cleaning them properly as a first step. Otherwise, you're looking at engine diagnostics, maybe an ECU issue, which will likely be workshop time.

Cheers. You were spot on. Took it to the shop, and it was the battery cable connections. Cleaned them up, and we're good to go. Cost me 155€. Thanks for the advice!