DTC P0403-00: EGR Valve Control Circuit Problem: Notes

DTC P0403:00 DETECTION CONDITION AND POSSIBLE CAUSE

DTC P0403:00	EGR valve control circuit problem
DETECTION CONDITION	The PCM monitors the input voltage from the EGR valve. If the voltage remain low or high, the PCM determines that the EGR valve circuit has a malfunction. Diagnostic support note This is a continuous monitor (CCM). The check engine light illuminates if the PCM detects the above malfunction condition during the first drive cycle. FREEZE FRAME DATA/Snapshot data is available. DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION	Inhibits the EGR control.
POSSIBLE CAUSE	EGR valve connectors or terminals malfunction Short to ground or open circuit in EGR valve power supply circuit Short to ground in wiring harness between the following terminals: ENGINE1 15 A fuse-EGR valve terminal C ENGINE1 15 A fuse-EGR valve terminal D ENGINE1 15 A fuse malfunction Open circuit in wiring harness between the following terminals: Main relay terminal C-EGR valve terminal C Main relay terminal C-EGR valve terminal D Short to ground in wiring harness between the following terminals: EGR valve terminal A-PCM terminal 1J EGR valve terminal E-PCM terminal 1Y EGR valve terminal B-PCM terminal 1O EGR valve terminal F-PCM terminal 1T PCM connector or terminals malfunction Short to power supply in wiring harness between the following terminals: EGR valve terminal A-PCM terminal 1J EGR valve terminal E-PCM terminal 1Y EGR valve terminal B-PCM terminal 1O EGR valve terminal F-PCM terminal 1T EGR valve circuits are shorted to each other Open circuit in wiring harness between the following terminals: EGR valve terminal A-PCM terminal 1J EGR valve terminal E-PCM terminal 1Y EGR valve terminal B-PCM terminal 1O EGR valve terminal F-PCM terminal 1T EGR valve malfunction PCM malfunction
Courtesy of MAZDA MOTORS CORP.