Dtc P0403 [Lf] - Mazda 3 Workshop Manual

Mazda 3 Workshop Manual – Engine + Wiring Diagrams + Diagnostic Trouble Codes
- CMP sensor terminal B (wiring
harness-side) and PCM terminal
2U (wiring harness-side)
• Is there continuity?
INSPECT CMP SENSOR
• Turn the ignition switch off.
• Perform CMP sensor inspection.
10
(See CAMSHAFT POSITION (CMP)
SENSOR INSPECTION
• Is the CMP sensor normal?
VERIFY TROUBLESHOOTING OF DTC
P0340 COMPLETED
• Make sure to reconnect all disconnected
connectors.
• Turn the ignition switch to the ON position
(Engine off).
• Clear the DTC from the PCM memory
using the WDS or equivalent.
11
• Start engine.
• Access MAF PID using the WDS or
equivalent.
Note
• MAF PID should indicate 1.95
g/s {0.25 lb/min} or above during
this test.
• Is the same DTC present?
VERIFY AFTER REPAIR PROCEDURE
• Perform the "After Repair Procedure".
12
(See AFTER REPAIR PROCEDURE
• Are any DTC present?
DTC P0403
DETECTION
CONDITION
Downloaded from
Yes Go to the next step.
No
[LF].)
Yes
No Go to the next step.
Yes
[LF].)
No Troubleshooting completed.

DTC P0403 [LF]

EGR valve (stepper motor) circuit problem
• The PCM monitors the input voltage from EGR valve. If voltage at PCM
terminals 2AU, 2AR, 2AY and/or 2AV remain low or high, the PCM
determines that the EGR valve circuit has malfunction.
Diagnostic support note
https://carmanualshub.com/
Inspect the CMP sensor pulse wheel for
damage. Replace CMP sensor pulse wheel and
go to step 10.
Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION
Go to the applicable DTC troubleshooting.
(See DTC TABLE [LF].)
- automotive repair manuals website
[LF].)
B3E010201086W01