Code 12 (HON0403AP)
Publication date: 1995-03-01Reference number: HON0403AP
CODE 12
TECHNICAL INFORMATION TIP
CODE 12
YEAR(S) 1984-94
MANUFACTURER: Honda
MODEL(S): All Models
DATE OF ISSUE: March, 1995
ISSUE & TIP
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