Ignition System - DTC P1381 Diagnostic Tips

Troubleshooting Tips for

DTC P1381

Troubleshooting a '98-02 Accord L4 or '96-00 Civic with DTC P1381 (CYP sensor intermittent interruption)? If you can't find anything wrong after following the procedure in the appropriate S/M, then try this:





1. Remove the distributor cap, and make sure the ignition coil shield is there and it's correctly installed.

^ If the ignition coil shield installation is right, go to step 2.

^ If the ignition coil shield installation isn't right, properly install the coil shield.

2. Unplug the 4P connector from the alternator

3. Test-drive the vehicle.

^ If DTC P1381 comes back with the alternator unplugged, replace the distributor housing.

^ If DTC P1381 doesn't come back, go to step 4.

4. Plug the 4P connector into the alternator, and use the HDS to do a charging system test. Look at the alternator diode pattern on the display screen.

^ If the diode pattern doesn't look right, replace the alternator. A faulty diode can cause electrical interference that sets this DTC.

^ If the diode pattern looks OK, press on with normal troubleshooting.