DTC P1530: Ignition Timing Adjustment Switch Circuit Malfunction
- Locate test connector next to coolant recovery bottle. Ensure test connector terminals are not grounded or jumpered. Repair as necessary. If test connector is okay, go to next step.
- Turn ignition on. Using DVOM, measure voltage between ground and test switch terminal (Blue/Red wire) at test connector. If voltage is 10-14 volts, check for an intermittent problem. See TESTS W/O CODES article. If voltage is not as specified, go to next step.
- Turn ignition off. Disconnect PCM harness connectors. Turn ignition on. On models equipped with 3-speed automatic or manual transmission, measure resistance between ground and terminal No. 6 (Blue/Red wire) at 22-pin PCM harness connector. On models equipped with 4-speed automatic transmission, measure resistance between ground and terminal No. 18 (Blue/Red wire) at 22-pin PCM harness connector. If continuity is present, repair short to ground in Blue/Red wire. If continuity is not present, replace PCM and retest system.