Ignition Coil Troubleshooting

NOTE: Do an ignition coil test after finishing the fundamental tests for the ignition system and the fuel and emissions system.

Disconnect the three ignition coil 3P connectors.
Measure the voltage at each ignition coil 3P connector terminal No. 3 with the ignition switch ON (II).

Fig 1: Measuring Voltage In Ignition Coil 3P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?
1. YES -Go to step 3.
2. NO -Repair an open in the wire between the ignition coil and the No. 7 (15 A) fuse in the under-dash fuse/relay box.
Turn the ignition switch OFF.
Check for continuity between each ignition coil 3P connector terminal No. 2 and body ground.

Fig 2: Checking Continuity Between Each Ignition Coil 3P Connector Terminal No. 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES -Go to step 5.
2. NO -Repair an open in the wire between the ignition coil and body ground (G101).
Disconnect ECM connector C (31P).
Check for continuity between the body ground and ECM connector terminals C4, C13, and C14 individually.

Fig 3: Checking Continuity Between Body Ground And ECM Connector Terminals C4, C13, And C14
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES -Repair a short in the wire between the ignition coil and the ECM.
2. NO -Go to step 7.
Connect the ECM connector C (31P).
Measure the voltage at each ignition coil 3P connector terminal No. 1 with the ignition switch in START (III).

Fig 4: Measuring Voltage In Ignition Coil 3P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 0.5 V?
1. YES -Replace the ignition coil.
2. NO -Repair an open in the wire between the ignition coil and the ECM.