DTC P1500: Engine Starter Signal Circuit Malfunction
WARNING: This page is about a different car, the 1997 Suzuki Sidekick. However, it is still accessible from the selected car via links, so may be relevant.
Turn ignition off. Disconnect PCM harness connectors. Turn ignition on. On models with 3-speed automatic or manual transmission, measure voltage between ground and PCM harness connector "C", terminal No. 2 (Black/Yellow wire). On models with 4-speed automatic transmission, measure voltage between ground and PCM harness connector "D", terminal No. 2 (Black/Yellow wire). If reading is 6-12 volts while cranking engine, check for poor connections at PCM. If connections are okay, replace PCM. If reading is not a specified, repair open Black/Yellow wire.