Mazda 626 - DTC P1504 (Except for GF4 A-EL Models);Diagnostic Procedure

ON-BOARD DIAGNOSTIC
DTC P1504
Except for GF4A-EL Models
DTC P1504
IAC valve circuit malfunction
DETECTION
CONDITION
• If PCM detects that PCM terminal 4M voltage is above threshold* or below threshold* when IAC
control duty target is within 18—70 %, PCM determines that IAC valve circuit has malfunction.
*:When detected the threshold value depends on battery voltage and IAC control signal duty value.
POSSIBLE
CAUSE
IAC valve circuit malfunction
Short to ground between IAC valve terminal A and PCM terminal 4M
Open circuit between IAC valve terminal A and PCM terminal 4M
Short to ground between IAC valve terminal B and PCM terminal 40
Short to power between IAC valve terminal B and PCM terminal 40
Open circuit between IAC valve terminal B and PCM terminal 40
Poor connection of IAC valve connector or PCM connector
PCM malfunction
PCM
IAC VALVE
IAC VALVE
HARNESS SIDE CONNECTOR
(VIEW FROM TERMINAL SIDE)
54
PCM
rrti th 1T7
M-,i,i,i,r 0i' i.i;i:i.i:t.i:i' r iv r T
83
7
HARNESS SIDE CONNECTOR
(VIEW FROM TERMINAL SIDE)
Diagnostic procedure
STEP INSPECTION ACTION
1
VERIFY RELATED REPAIR INFORMATION
AVAILABILITY
• Check for related Service Information
availability.
• Is any service Information available?
Yes Perform repair or diagnosis according to available
Service Information.
• If vehicle is not repaired, then go to next step.
No
Go to next step.
2 CLASSIFY INTERMITTENT CONCERN OR
CONTINUOUS CONCERN
• Clear DTC from memory using NGS tester.
• Start engine and warm it up completely.
• Is same DTC detected?
Yes
Go to next step.
No
Go to intermittent concern.
(See F1-142 No.26 INTERMITTENT CONCERNS)
F1-80