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Code 12 (HON0403AP)

Publication date: 1995-03-01
Reference number: HON0403AP

CODE 12

CODE 12

TECHNICAL INFORMATION TIP

Reference Number(s): HON0403AP, Date of Issue:  March, 1995

CODE 12

YEAR(S) 1984-94

MANUFACTURER: Honda

MODEL(S): All Models

DATE OF ISSUE: March, 1995

ISSUE & TIP

NOTE: Only certain 84-86 Hondas have an ECM.

A PGM light and a Code 12 on late model Hondas may be caused by a partially stuck open EGR control vent solenoid. The trouble may be intermittent and the code may not be set.

Test the system by pinching hose 17 with the engine running. The engine should stumble as the EGR opens. Also check to see whether the EGR opens with regular operation at 2500 RPM.

If not, ground the pink wire at the two wire connector in the vacuum control box (located at the right side of the firewall). The engine should stumble. If the engine doesn't stumble, remove the EGR control solenoid from the vacuum box, then clean or replace it.

Courtesy of Import Service Magazine

with thanks to:

Paul Brow

All Car Specialist, Inc.

San Gabriel, California

REFERENCE NUMBER

HON0403AP

NOTE: This information has been obtained from sources generally believed to be reliable. Use your own judgment before relying on this data. Neither the suppliers of these Technical Information Tips, nor lemon-25 Repair Information Company, LLC, guarantees or assumes responsibility for data accuracy or completeness, nor is liability assumed by the suppliers of these Technical Information Tips or lemon-25 Repair Information Company, LLC, for any claims or damages resulting from the use of this information.