Toyota 90080-19012 Ignition Coil Assembly

The following coil primary and secondary resistance checks do not apply to the ignition coil/igniter units used on 2001 and later models, as the manufacturer does not publish specifications for these units. The only way to check them is by substituting a known good unit, which is not feasible for a home mechanic due to the inability to return electrical components once purchased. If all other possible causes of an ignition malfunction have been eliminated, a defective ignition coil/igniter unit is likely the issue, and verification requires a dealer's assistance. Resistance checks should be performed with the engine cold, as hot engines will show greater resistance. For 1998 through 2000 models, check the primary resistance by disconnecting the electrical harness from each coil and measuring across the coil primary terminals with an ohmmeter; replace the coil if readings are not within specifications. For secondary resistance, detach the spark plug wires and remove the coil to measure across the two secondary terminals; again, replace if readings are not acceptable. If no specifications are available, compare readings from several coils or swap them between cylinders. To replace the ignition coil, disconnect the negative battery cable, remove the V-bank cover, and on 2007 and later models, the upper intake manifold. Disconnect the ignition coil harness connectors from each coil pack, labeling them to avoid confusion, and detach the spark plug wires for the rear cylinder bank. Remove the bolts securing the ignition coil to the engine and take out the coil, then installation follows the reverse of the removal process.

Label and detach the spark plug wires from each coil and connect an ohmmeter across the two secondary terminals of each coil.

A defective ignition coil/igniter unit is likely the cause.