Spark Test: Highlander
- Check for any diagnostic trouble codes. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article for retrieving of DTCs. If no DTCs exist, go to next step. If any DTCs exist, perform service procedure for DTC.
- Remove ignition coils. See IGNITION COIL under IGNITION SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - V6 & V8 article. Remove spark plugs. Install spark plug on each ignition coil. Reinstall electrical connectors on ignition coils. Ground spark plugs against cylinder block.
- Disconnect electrical connectors at fuel injectors. Crank engine and check for spark. If spark exists only at some spark plugs and not at other spark plugs, go to next step. If spark does not exist at any spark plug, go to step 5. If spark exists at all spark plugs, reinstall components. Tighten spark plugs to 13 ft. lbs. (18 N.m).
- Install substitute spark plug in which spark does not exist and recheck for spark. If spark now exists, replace original spark plug. If spark still does not exist, replace ignition coil. Reinstall components. Tighten spark plugs to 13 ft. lbs. (18 N.m).
- Install substitute spark plugs and recheck for spark. If spark now exists, replace original spark plugs. If spark still does not exist, replace ignition coil that does not produce spark. Reinstall components. Tighten spark plugs to 13 ft. lbs. (18 N.m).
CAUTION:
To prevent gasoline from being injected, electrical connectors should be disconnected from fuel injectors. DO NOT crank engine for longer than 2 seconds when checking for spark.