DTC P1500 - Engine Starter Signal Circuit Malfunction
WARNING: This page is about a different car, the 1996 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. Using a voltmeter, measure voltage between ground and PCM harness connector "C", terminal No. 2 (Black/Yellow wire). See Figure . 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.